Fall Gelb and the Dunkirk Debacle
Following the invasion of Poland in August 1939 a period of inaction called the Phony War (“Sitzkrieg” or “Drôle de guerre”) set in between the major powers. Hitler had hoped that France and the United Kingdom would acquiesce in his conquest and quickly make peace. This was essential to him because Germany’s stock of raw materials—and of the foreign currencies to buy them—was critically low. He was now dependent on supplies from the Soviet Union, a situation with which he was uncomfortable for ideological reasons. On 6 October he made a peace offer to both Western Powers. Even before they had had time to respond, on 9 October he also formulated a new military policy in case their reply was negative: Führer-Anweisung N°6, or “Führer-Directive Number 6”.
Hitler had always fostered dreams about major military campaigns to defeat the Western European nations as a preliminary step to the conquest of territory in the East, thus avoiding a two-front war. However, these intentions were absent from Führer-Directive N°6. This plan was firmly based on the seemingly more realistic assumption that Germany’s military strength would still have to be built up for several more years and that for the moment only limited objectives could be envisaged. They were aimed at improving Germany’s ability to survive a long, protracted war in the West. Hitler ordered a conquest of the Low Countries (the Netherlands, Belgium and Luxembourg) to be executed at the shortest possible notice. This would prevent France from occupying them first, which would threaten the vital German Ruhr Area. It would also provide the basis for a successful long-term air and sea campaign against the United Kingdom. There was no mention in the Führer-Directive of any immediate consecutive attack to conquer the whole of France, although as much as possible of the border areas in northern France should be occupied.
While writing the directive, Hitler had assumed that such an attack could be initiated within a period of at most a few weeks, but the very day he issued it he was disabused of this illusion. It transpired that he had been misinformed about the true state of Germany’s forces. The motorized units had to recover, repairing the damage to their vehicles incurred in the Polish campaign; ammunition stocks were largely depleted. There was also evidence that there had been instances of indiscipline in the German Army and some panic under fire, something that the German Army Staff said needed to be addressed before another large scale military offensive was launched.
The Schlieffen Plan revisited?
On 10 October 1939, the British refused Hitler’s offer of peace; on 12 October the French did the same. Franz Halder, the chief of staff of the OKH, the German Army High Command, presented the first plan for Fall Gelb (“Case Yellow”) on 19 October, the pre-war codename of plans for campaigns in the Low Countries: the Aufmarschanweisung N°1, Fall Gelb, or “Deployment Instruction No. 1, Case Yellow”. Halder’s plan has often been compared to the Schlieffen Plan, which the Germans executed in 1914 during the Great War. It was similar in that both plans entailed an advance through the middle of Belgium, but while the intention of the Schlieffen Plan was to gain a decisive victory by executing a surprise encirclement of the French army, Aufmarschanweisung N°1 was based on an unimaginative frontal attack, sacrificing a projected half a million German soldiers to attain the limited goal of throwing the Allies back to the River Somme. Germany’s strength for 1940 would then be spent; only in 1942 could the main attack against France begin.
Hitler was very disappointed with Halder’s plan. He had assumed that the conquest of the Low Countries could be quick and cheap, but as it was presented, it would be long and difficult. It has even been suggested that Halder, who was at the time conspiring against Hitler and had begun carrying a revolver with the intention of shooting him, proposed the most pessimistic plan possible to discourage Hitler from the attack entirely. Hitler reacted in two ways. He decided that the German army should attack early, ready or not, in the hope that Allied unpreparedness might bring about an easy victory. He set the date for 12 November 1939. This led to an endless series of postponements, as time and again commanders managed to convince Hitler that the attack should be further delayed for a few days or weeks to remedy some critical defect in the preparations, or to wait for better weather conditions. Secondly, because the plan as it was did not appeal to him, he tried to make it different, without clearly understanding in which way it could be improved. This mainly resulted in a dispersion of effort, since besides the main axis in central Belgium, secondary attacks were foreseen further south. On 29 October, Halder let a second operational plan, Aufmarschanweisung N°2, Fall Gelb, reflect these changes by featuring a secondary attack on the Netherlands.
Criticism by German Generals
Hitler was not alone in disliking Halder’s plan. General Gerd von Rundstedt, the commander of Army Group A, also disagreed with it. Unlike Hitler, von Rundstedt, as a professional soldier, understood perfectly well how it should be rectified. Its fundamental flaw was that it did not conform to the classic principles of the Bewegungskrieg, or “maneuver warfare”, that had been the basis of German tactics since the 19th century. A breakthrough would have to be accomplished that would result in the encirclement and destruction of the main body of Allied forces. The logical place to achieve this would be the Sedan axis, which lay in the sector of von Rundstedt’s Army Group A. On 21 October, von Rundstedt agreed with his chief of staff, Lieutenant-General Erich von Manstein, that an alternative operational plan had to be arranged that would reflect these basic ideas, making his Army Group A as strong as possible at the expense of Army Group B to the north.
The Manstein Plan
Whilst von Manstein was formulating new plans in Koblenz, Lieutenant-General Heinz Guderian, commander of the XIXth Army Corps, Germany’s elite armored formation, happened to be lodged in a nearby hotel. Von Manstein now considered that, should he involve Guderian in his planning, the tank general might come up with some role for his Army Corps to play, and this might then be used as a decisive argument to relocate XIXth Army Corps from Army Group B to Army Group A, much to the delight of von Rundstedt.
At this moment von Manstein’s plan consisted of a move from Sedan in the north, to the rear of the main Allied forces, to engage them directly from the south in full battle. When Guderian was invited to contribute to the plan during informal discussions, he proposed a radical and novel idea. Not only his army corps, but the entire Panzerwaffe should be concentrated at Sedan. This concentration of armor should subsequently not move to the north but to the west, to execute a swift, deep, independent strategic penetration towards the English Channel without waiting for the main body of infantry divisions. This could lead to a strategic collapse of the enemy, avoiding the relatively high number of casualties normally caused by a classic Kesselschlacht or “annihilation battle”. Such a risky independent strategic use of armor had been widely discussed in Germany before the war but had not been accepted as received doctrine; the large number of officers serving in the Infantry, which was the dominant Arm of Service, had successfully prevented this. Von Manstein had to admit that in this special case, however, it might be just the thing needed. His main objection was that it would create an open flank of over 300 kilometers, vulnerable to French counterattack. Guderian convinced him that this could be prevented by launching simultaneous spoiling attacks to the south by small armored units. However, this would be a departure from the basic concept of the Führer-Directive N°6.
Von Manstein wrote his first memorandum outlining the alternative plan on 31 October. In it he carefully avoided mentioning Guderian’s name and downplayed the strategic part of the armored units, in order to not generate unnecessary resistance. Six more memoranda followed between 6 November 1939 and 12 January 1940, slowly growing more radical in outline. All were rejected by the OKH and nothing of their content reached Hitler.
In the winter of 1939–1940, the Belgian consul-general in Cologne had anticipated the angle of advance that Von Manstein was planning. They deduced, through intelligence reports, that German forces were concentrating along the Belgian and Luxembourg frontiers. The Belgians were convinced that the Germans would thrust through the Ardennes and to the English Channel with the aim of cutting off the Allied field Armies in Belgium and north-eastern France. Such warnings were not heeded by the French.
On 10 January 1940, a German Messerschmitt Bf 108 made a forced landing at Maasmechelen, north of Maastricht, in Belgium. Among the occupants of the aircraft was a Luftwaffe major, Hellmuth Reinberger, who was carrying a copy of the latest version of Aufmarschanweisung N°2. Reinberger was unable to destroy the documents, which quickly fell into the hands of the Belgian intelligence services. It has often been suggested that this incident was the cause of a drastic change in German plans, but this is incorrect; in fact a reformulation of them on 30 January, Aufmarschanweisung N°3, Fall Gelb, conformed to the earlier versions. On 27 January, von Manstein was relieved of his appointment as Chief of Staff of Army Group A and appointed commander of an army corps in Prussia, to begin his command in Stettin on 9 February. This move was instigated by Halder to reduce von Manstein’s influence. Von Manstein’s indignant staff then brought his case to Hitler’s attention, who was informed of it on 2 February. Von Manstein was invited to explain his proposal to the Führer personally in Berlin on 17 February. Hitler was much impressed by it, and the next day he ordered the plans to be changed in accordance with von Manstein’s ideas. They appealed to Hitler mainly because they offered some real hope of a cheap victory.
The man who had to carry out the change was again Franz Halder—von Manstein was not further involved. Halder consented to shifting the main effort, the Schwerpunkt, to the south. Von Manstein’s plan had the virtue of being unlikely (from a defensive point of view) since the Ardennes were heavily wooded and contained a poor road network, making them implausible as a route for invasion. An element of surprise would therefore be present. It would be essential that the Allies respond as envisaged in the original plans, namely that the main body of French and British troops would be drawn north to defend Belgium. To help to ensure this condition, Army Group B had to execute a holding attack in Belgium and the Netherlands, giving the impression of being the main German effort, in order to draw Allied forces eastward into the developing encirclement and hold them there. To accomplish this, three of the ten available armored divisions were still allocated to Army Group B.
Halder had no intention of deviating from established doctrine by allowing an independent strategic penetration by the seven armored divisions of Army Group A. Much to the outrage of Guderian, this element was at first completely removed from the new plan, Aufmarschanweisung N°4, Fall Gelb, issued on 24 February. The crossings of the River Meuse at Sedan should be forced by infantry divisions on the eighth day of the invasion. Only after much debate was this changed to allow the motorized infantry regiments of the armored divisions to establish bridgeheads on the fourth day, to gain four days. Even now the breakout and drive to the English Channel would start only on the ninth day, after a delay of five days during which a sufficient number of infantry divisions had to be built up in order to advance together with the armored units in a coherent mass.
Even when adapted to more conventional methods, the new strategy provoked a storm of protest from the majority of German generals. They thought it utterly irresponsible to create a concentration of forces in a position where they could not possibly be sufficiently supplied, while such inadequate supply routes as there were could easily be cut off by the French. If the Allies did not react as expected the German offensive could end in catastrophe. Their objections were ignored. Halder argued that, as Germany’s strategic position seemed hopeless anyway, even the slightest chance of a decisive victory outweighed the certainty of ultimate defeat implied by inaction. The adaptation also implied that it would be easier for the Allied forces to escape to the south. Halder pointed out that if so, Germany’s victory would be even cheaper, while it would be an enormous blow to the reputation of the Entente, to have abandoned the Low Countries. Moreover Germany’s fighting power would then still be intact, so that it might be possible to execute Fall Rot, the main attack on France, immediately afterwards. However, a decision to this effect would have to be postponed until after a possible successful completion of Fall Gelb. Indeed, German detailed operational planning only covered the first nine days; there was no fixed timetable established for the advance to the Channel. In accordance with the tradition of the Auftragstaktik, much would be left to the judgment and initiative of the field commanders. This indetermination would have an enormous effect on the actual course of events.
In April 1940, for strategic reasons, the Germans launched Operation Weserübung, an attack on the neutral countries of Denmark and Norway. The British, French, and Free Poles responded with an Allied campaign in Norway in support of the Norwegians.
The Allied Strategy
In September 1939, Belgium and the Netherlands were still neutral. They had made arrangements in secret with the Entente for future cooperation should the Germans invade their territory. The Supreme Commander of the French Army, Maurice Gamelin, suggested during that month that the Allies should take advantage of the fact that Germany was tied up in Poland by occupying the Low Countries before Germany could. This suggestion was not taken up by the French government.
In September 1939, in the Saar Offensive—only made to nominally fulfill the prewar guarantee to Poland to execute a relief attack from the West—French soldiers advanced 5 kilometers (3.1 mi) into the Saar before withdrawing in October. At this time, France had employed 98 divisions (all but 28 of them reserve or fortress formations) and 2,500 tanks against German forces consisting of 43 divisions (32 of them reserves) and no tanks. According to the judgment of Wilhelm Keitel, then Chief of OKW, the French army would easily have been able to penetrate the mere screen of German forces present.
After October, it was decided not to take the initiative in 1940, although important parts of the French army in the 1930s had been designed to wage offensive warfare. The Allies believed that even without an Eastern Front the German government might be destabilized by a blockade, as it had been in the Great War. In the event that the Nazi regime did not collapse, during 1940 a vast modernization and enlargement programme for the Allied forces would be implemented, exploiting the existing advantages over Germany in war production to build up an overwhelming mechanized force, including about two dozen armored divisions. This was to execute a decisive offensive in the summer of 1941. Should the Low Countries by that date still not have committed themselves to the Allied cause, the Entente firmly intended to violate their neutrality if necessary.
Obviously the Germans might strike first, and a strategy would have to be prepared for this eventuality. Neither the French nor the British had anticipated such a rapid German victory in Poland, which they found disturbing. Most French generals favored a very cautious approach. They thought it wise not to presume that German intentions could be correctly predicted. A large force should be held in reserve in a central position, north of Paris, to be prepared for any contingency. Should the Germans take the obvious route through Flanders, they should only be engaged in northern France, when their infantry was exhausted and they had run out of supplies. If they tried an attack on the center of the Allied front, the Allied reserve would be ideally positioned to block it. If the Germans advanced through Switzerland, a large reserve would be the only means to deal with such a surprise.
The Dyle Plan
Gamelin rejected this line of thought, for several reasons. The first was that it was politically unthinkable to abandon the Low Countries to their fate, however prudent it might be from an operational point of view. Secondly, the British government insisted that the Flemish coast remain under Allied control. The third reason was that the 1941 offensive had no chance of success if it had to be launched from the north of France against German forces entrenched in central Belgium. The German offensive had to be contained as far east as possible. Finally, and for him personally, the most cogent argument was that Gamelin did not consider the French army capable of winning a mobile battle against the German army. French infantry divisions as yet were insufficiently motorized. The events in Poland helped confirm his opinion. Such a confrontation had to be avoided at all costs. Gamelin intended to send the best units of the French army along with the British Expeditionary Force north to halt the Germans at the KW-line. This was a defensive line that followed the river Dyle, east of Brussels, in a coherent tightly packed continuous front uniting the British, Belgian and French armies. This plan presumed that the Germans planned to concentrate their forces where they could be well supplied by the better road network of northern Belgium.
Gamelin did not have the personality to simply impose his will. The first step he took was to propose the “Escaut” variant as an option for Plan D (the codename for an advance into the Low Countries). It was named after the river in Flanders. Protecting the Flemish coast seemed the least one could do; on the other hand it created an enormous salient, showing that it made more sense to defend along the shorter Dyle line, which was precisely the content of Gamelin’s next proposal in November, after he had become confident the Belgians would be able to delay the Germans sufficiently. This was, however, too transparent. His second “Dyle Plan” met with strong opposition, which did not grow any less when the Mechelen crash, in January 1940, confirmed that the German plans conformed to Gamelin’s expectations. Also, General Lord Gort, the commander of the British Expeditionary Force, was beginning to expect that whatever the Germans came up with would not be what he had initially predicted. The main objection was that the maneuver was very risky. The Allied forces had to complete their advance and entrenchment before the Germans reached the Dyle line, for which there seemed to be barely enough time. When entrenched they would have trouble reacting to German strategic surprises, because their fuel supplies would also have to be replenished. The next problem was that this line was very vulnerable to the German main strength and their large tactical bomber force.
Gamelin successfully countered these arguments by adopting the seemingly reasonable assumption that the Germans would try to attempt a breakthrough by concentrating their mechanized forces. They could hardly hope to break the Maginot Line on his right flank or to overcome the Allied concentration of forces on the left flank. That only left the center, but most of the center was covered by the river Meuse. Tanks were useless in defeating fortified river positions. However, at Namur the river made a sharp turn to the east, creating a gap between itself and the river Dyle. This ‘Gembloux Gap’, ideal for mechanized warfare, was a very dangerous weak spot. Gamelin decided to concentrate half of his armored reserves there. By thus assuming that the decisive moment in the campaign would take the form of a gigantic tank battle, he avoided the problem of the German tactical bomber force since air attacks were considered less effective against mobile armored units, the tanks of which would be hard to hit. Of course the Germans might try to overcome the Meuse position by using infantry, but that could only be achieved by massive artillery support, the gradual build-up of which would give Gamelin ample warning to allow him to reinforce the Meuse line.
During the first months of 1940 the size and readiness of the French army steadily grew, and Gamelin began to feel confident enough to propose a somewhat more ambitious strategy. He had no intention of frontally attacking the German fortification zone, the Westwall, in 1941, planning instead to outflank it from the north. To achieve this, it would be most convenient if he already had a foothold on the north bank of the Rhine, so he changed his plans to the effect that a French army should maintain a connection north of Antwerp with the Dutch National Redoubt, “Fortress Holland”. He assigned his sole strategic reserve, the French Seventh Army, to this task. His only reserves now consisted of individual divisions. Again there was much opposition to this “Dyle-Breda-Plan” within the French army, but Gamelin was strongly supported by the British government, because Holland proper was an ideal base for a German air campaign against Britain.
Forces and Dispositions
Germany deployed about three million men for Fall Gelb. Conscription had not been allowed by the Treaty of Versailles from 1919, a provision which the German government had repudiated as recently as 1935. In May 1940 only 79 divisions out of a total of 157 raised had completed their training; another fourteen were nevertheless directly committed to battle, mainly in Army Group C and against the Netherlands. Beside this total of 93 front-line divisions (ten armored, six motorized) there were also 39 OKH reserve divisions in the West, about a third of which would not be committed to battle. About a quarter of the combat troops consisted of veterans from the First World War, older than forty.
The German forces in the West would in May and June deploy some 2,700 tanks and self-propelled guns, including matériel reserves committed; about 7,500 artillery pieces were available with ammunition stocks sufficient for six weeks of fighting. The Luftwaffe divided its forces into two groups. 1,815 combat, 487 Transport and 50 Glider aircraft were deployed to support Army Group B, while a further 3,286 combat aircraft were deployed to support Army Groups A and C.
The German Army was divided into three army groups:
- Army Group A commanded by Gerd von Rundstedt, composed of 45½ divisions including seven armored, was to execute the decisive movement, cutting a “Sichelschnitt”—not the official name of the operation but the translation in German of a phrase after the events coined by Winston Churchill as “Sickle Cut” (and even earlier “armored scythe stroke”)—through the Allied defenses in the Ardennes. It consisted of three armies: the Fourth, Twelfth and Sixteenth. It had three Panzer corps; one, the XVth, had been allocated to the Fourth Army, but the other two (the XXXXIst, including the 2nd Motorized Infantry Division and the XIXth) were united with the XIVth Army Corps of two motorized infantry divisions, on a special independent operational level in Panzergruppe Kleist. This was done to better coordinate the approach march to the Meuse; once bridgeheads had been established across the river, the Panzer Group headquarters would be disbanded and its three corps would be divided between the Twelfth and Sixteenth Armies.
- Army Group B under Fedor von Bock, composed of 29½ divisions including three armored, was tasked with advancing through the Low Countries and luring the northern units of the Allied armies into a pocket. It consisted of the Sixth and Eighteenth Armies.
- Army Group C, composed of 18 divisions under Wilhelm Ritter von Leeb, was charged with preventing a flanking movement from the east, and with launching small holding attacks against the Maginot Line and the upper Rhine. It consisted of the 1st and 7th Armies.
Due to a low birthrate, which had further declined during the First World War and the Great Depression, France had a severe manpower shortage relative to its total population, which furthermore was barely half that of Germany. To compensate, France had mobilized about a third of the male population between the ages of 20 and 45, bringing the strength of its armed forces to over six million men, more than the entire German Wehrmacht of 5.4 million. Only 2.2 million of these served in army units in the north, although the total there was brought to over 3.3 million by the Belgian, British and Dutch forces. On 3 May there were 93 French, 22 Belgian, 10 British and nine Dutch divisions in the North, a total of 134. Six of these were armored, 24 were motorized. Twenty-two more divisions were being trained or assembled on an emergency basis during the campaign (not counting the reconstituted units), among which were two Polish and one Czech division. Beside full divisions the Allies had many independent smaller infantry units: the Dutch had the equivalent of about eight divisions in independent brigades and battalions; the French had 29 independent Fortress Infantry Regiments. Of the French divisions, eighteen were manned by colonial volunteer troops; nineteen consisted of “B-divisions”, once fully trained units that had a large number of men over thirty and needed retraining after mobilization. The best trained Allied forces were the British divisions, fully motorized with a large percentage of professional soldiers; the worst the very poorly equipped Dutch troops.
The Allied forces deployed an organic strength of about 3,100 modern tanks and self-propelled guns on 3 May; another 1,200 were committed to battle in new units or from the matériel reserves; 1,500 obsolete FT-17 tanks were also sent to the front for a total of about 5,800. They had about 14,000 artillery pieces. The Allies thus enjoyed a clear numerical superiority on the ground but were inferior in the air: the French Armee de l’Air had 1,562 aircraft, and RAF Fighter Command committed 680 machines, while RAF Bomber Command could contribute some 392 aircraft to operations. Most of the Allied aircraft were obsolete types; among the fighter force only the British Hawker Hurricane and the French Dewoitine D.520 could contend with the German Messerschmitt Bf 109 on something approaching equal terms.
At the beginning of Fall Rot, the French aviation industry had reached a considerable output, with an estimated matériel reserve of nearly 2,000 aircraft. However, a chronic lack of spare parts crippled this stocked fleet. Only 29% (599) of the aircraft were serviceable, of which 170 were bombers.
The French forces in the north had three Army Groups: the Second and the Third defended the Maginot Line to the east; the First Army Group under Gaston-Henri Billotte was situated in the west and would execute the movement forward into the Low Countries. The French Seventh Army on the coast, was reinforced by a Light Mechanized (armored) division (DLM). The Seventh Army was intended to move to the Netherlands via Antwerp. Next to the south were the nine divisions of the British Expeditionary Force (BEF), which would advance to the Dyle Line and position itself to the right of the Belgian army. The French 1st Army, reinforced by two Light Mechanized Divisions, with a Reserve Armored Division (DCR) in reserve, would defend the Gembloux Gap. The southernmost army involved in the move forward into Belgium was the French Ninth Army, which had to cover the entire Meuse sector between Namur and Sedan. At Sedan, the French Second Army would form the “hinge” of the movement and remain entrenched.
The First Army Group had 35 French divisions; the total of 40 divisions of the other Allies in its sector brought their forces equal in number to the combined German forces of Army Group A and B. However, the former only had to confront the 18 divisions of the Ninth and Second Armies, and thus would have a large local superiority. To reinforce a threatened sector Gamelin had sixteen strategic reserve divisions available on General Headquarters level, two of them armored. These were “reserve” divisions in the operational sense only, consisting of high quality troops—most of them had been active divisions in peace-time, and were thus not comparable to the German reserve divisions that were half-trained. Confusingly, all mobilized French divisions were officially classified as A or B “reserve divisions,” although most of them served directly in the front armies.
Fall Gelb, Low Countries and Northern France
Germany initiated Fall Gelb on the evening prior to and the night of 3 May 1940. During the late evening of 2 May, German forces occupied Luxembourg. Army Group B launched its (feint) offensive during the night into the Netherlands and Belgium. Fallschirmjäger (paratroopers) from the 7th Flieger and 22. Luftlande Infanterie-Division under Kurt Student executed that morning surprise landings at the Hague, on the road to Rotterdam and against the Belgian fort at Eben-Emael in order to facilitate Army Group B’s advance.
The French command reacted immediately, sending its First Army Group north in accordance with Plan D. This move committed their best forces, diminishing their fighting power by the partial disorganization it implied and their mobility by depleting their fuel stocks. That evening the French Seventh Army crossed the Dutch border, only to find the Dutch already in full retreat. The French and British air command were less effective than their commanders had anticipated, and the Luftwaffe quickly gained air superiority, depriving the Allies of key reconnaissance abilities and disrupting Allied communications and coordination.
The Luftwaffe was guaranteed air superiority over the Netherlands. They allocated 247 medium bombers, 147 fighter aircraft, 424 transports, and 12 seaplanes to direct operations over the Netherlands. The Dutch Air Force, the Militaire Luchtvaartafdeling (ML), had a strength of 144 combat aircraft, half of which were destroyed within the first day of operations. The remainder was dispersed and accounted for only a handful of Luftwaffe aircraft shot down. In total the ML flew a mere 332 sorties losing 110 of its aircraft.
The German 18th Army secured all the strategically vital bridges in and toward Rotterdam, which penetrated Fortress Holland and bypassed the New Water Line from the south. However, an operation organized separately by the Luftwaffe to seize the Dutch seat of government, known as the Battle for The Hague, ended in complete failure. The airfields surrounding the city (Ypenburg, Ockenburg, and Valkenburg) were taken with heavy casualties and transport aircraft losses, only to be lost that same day to counterattacks by the two Dutch reserve infantry divisions. The Dutch captured or killed 1,745 Fallschirmjäger, shipping 1,200 prisoners to England.
The Luftwaffe’s Transportgruppen also suffered heavily. Transporting the German paratroops had cost it 125 Ju 52s destroyed and 47 damaged, representing 50 percent of the fleet’s strength. Most of these transports were destroyed on the ground, and some whilst trying to land under fire, as German forces had not properly secured the airfields and landing zones.
The French Seventh Army failed to block the German armored reinforcements from the 9th Panzer Division, which reached Rotterdam on 6 May. That same day in the east, following the Battle of the Grebbeberg in which a Dutch counter-offensive to contain a German breach had failed, the Dutch retreated from the Grebbe line to the New Water Line.
The Dutch Army, still largely intact, surrendered in the evening of 7 May after the Bombing of Rotterdam by Heinkel He 111s of Kampfgeschwader 54. It considered its strategic situation to have become hopeless and feared further destruction of the major Dutch cities. The capitulation document was signed on 8 May. However, the Dutch troops in Zeeland and the colonies continued the fight while Queen Wilhelmina established a government-in-exile in Britain.
The Germans were able to establish air superiority in Belgium with ease. Having completed thorough photographic reconnaissance missions, they destroyed 83 of the 179 aircraft of the Aeronautique Militaire within the first 24 hours. The Belgians would fly 77 operational missions but would contribute little to the air campaign. The Luftwaffe was assured air superiority over the Low Countries.
Because Army Group B had been so weakened compared to the earlier plans, the feint offensive by the German 6th Army was in danger of stalling immediately, since the Belgian defenses on the Albert Canal position were very strong. The main approach route was blocked by Fort Eben-Emael, a large fortress then generally considered the most modern in the world, controlling the junction of the Meuse and the Albert Canal. Any delay might endanger the outcome of the entire campaign, because it was essential that the main body of Allied troops was engaged before Army Group A would establish bridgeheads.
To overcome this difficulty, the Germans resorted to unconventional means in the assault on the fort learned from Oscarborg fortress. In the early hours of 3 May gliders landed on the roof of the fort and unloaded assault teams that disabled the main gun cupolas with hollow charges. The bridges over the canal were seized by German paratroopers. Shocked by a breach in its defenses just where they had seemed the strongest, the Belgian Supreme Command withdrew its divisions to the KW-line five days earlier than planned. At that time the BEF and the French 1st Army were not yet entrenched. When Erich Hoepner’s XVIth Panzer Corps, consisting of 3rd and 4th Panzer Divisions was launched over the newly-captured bridges in the direction of the Gembloux Gap, this seemed to confirm the expectations of the French Supreme Command that the German Schwerpunkt would be at that point. The two French Light Mechanized divisions, the 2nd DLM and 3rd DLM were ordered forward to meet the German armor and cover the entrenchment of the First Army. The resulting Battle of Hannut, which took place on 5 and 6 May was the largest tank battle until that date, with about 1,500 armored fighting vehicles participating.
The French claimed to have disabled about 160 German tanks for 91 Hotchkiss H35 and 30 Somua S35 tanks destroyed or captured. The Germans controlled the battlefield area afterwards, they recovered and eventually repaired or rebuilt many of the Panzers: German irreparable losses amounted to 49 tanks (20 3PD and 29 4PD). The German armor sustained substantial breakdown rates making it impossible to ascertain the exact number of tanks disabled by French action.
On the second day the Germans managed to breach the screen of French tanks, which were successfully withdrawn on 7 May to Gembloux after having gained enough time for the First Army to dig in. Hoepner tried to break the French line on 8 May against orders, leading to the Battle of Gembloux. This was the only time in the campaign when German armor frontally attacked a strongly held fortified position. The attempt was repelled by the 1st Moroccan Infantry Division, costing 4th Panzer Division another 42 tanks, 26 of which were irreparable. This French defensive success was made irrelevant by events further south.
In the center, the progress of German Army Group A was to be delayed by Belgian motorized infantry and French Mechanized Cavalry divisions (Divisions Légères de Cavalerie) advancing into the Ardennes. These forces had an insufficient anti-tank capacity to block the surprisingly large number of German tanks they encountered and quickly gave way, withdrawing behind the Meuse. The German advance was greatly hampered by the sheer number of troops trying to force their way along the poor road network. Kleist’s Panzer Group had more than 41,000 vehicles. This huge armada had been granted only four march routes through the Ardennes. The time-tables proved to be wildly optimistic and there was soon heavy congestion, beginning well over the Rhine to the east—it would last for almost two weeks. This made Army Group A very vulnerable to French air attacks, but these did not materialize.
Although Gamelin was well aware of the situation, the French tactical bomber force was far too weak to challenge German air superiority so close to the German border. On 4 May Gamelin ordered many reserve divisions to begin reinforcing the Meuse sector. Because of the danger the Luftwaffe posed, movement over the rail network was limited to night-time, slowing the reinforcement; but the French felt no sense of urgency as the build-up of German divisions would be correspondingly slow.
The German advance forces reached the Meuse line late in the afternoon of 5 May. To allow each of the three armies of Army Group A to cross, three major bridgeheads were to be established at: Sedan in the south, Monthermé twenty kilometers to the northwest and Dinant another fifty kilometers to the north. The first units to arrive hardly had local numerical superiority; their already insufficient artillery support was further limited by an average supply of just twelve rounds per gun.
The German Breakthrough at Sedan
At Sedan the Meuse Line consisted of a strong defensive belt, six kilometers deep according to the modern principles of zone defense on slopes overlooking the Meuse valley and strengthened by 103 pillboxes, manned by the 147th Fortress Infantry Regiment. The deeper positions were held by the 55th Infantry Division (55e DI). This was only a grade “B” reserve division, but already reinforcements were arriving. On the morning of 6 May, 71e DI was inserted to the east of Sedan, allowing 55e DI to narrow its front by a third and deepen its position to over ten kilometers. Furthermore, it had a superiority in artillery to the German units present. The French command fully expected that the Germans would only attack such formidable defenses when a large infantry and artillery force had been built up, a concentration that apparently could not be completed before 13 May, given the traffic congestion; a date very similar to Halder’s original projection. It thus came as a complete surprise when crossing attempts were made as early as the fourth day of the invasion.
The Luftwaffe’s Contribution to the Breakthrough
On 6 May, the German XIXth Corps forced three crossings near Sedan, executed by the motorized infantry regiments of the 1st, 2nd and 10th Panzer Divisions, reinforced by the elite Großdeutschland infantry regiment. Instead of slowly massing artillery as the French expected, the Germans concentrated most of their tactical bomber force to smash a hole in a narrow sector of the French lines by carpet bombing punctuated by dive bombing. Hermann Göring had promised Guderian that there would be extraordinarily heavy air support during a continual eight hour air attack, from 8am until dusk. Luftflotte 3, supported by Luftflotte 2, executed the heaviest air bombardment the world had yet witnessed and the most intense by the Luftwaffe during the war. The Luftwaffe committed two Stukageschwader to the assault, flying 300 sorties against French positions, with Stukageschwader 77 alone flying 201 individual missions. A total of 3,940 sorties were flown by nine Kampfgeschwader, often in Gruppe strength.
The forward platoons and pillboxes of the 147 RIF were little affected by the bombing and held their positions throughout most of the day, initially repulsing the crossing attempts of the 2nd and 10th Panzer Divisions on their left and right. However, there was a gap in the line of bunkers in the center of the river bend. In the late afternoon Großdeutschland penetrated this position, trying to quickly exploit the opportunity. The deep French zonal defense had been devised to defeat just these kind of infiltration tactics; it now transpired that the morale of the deeper company positions of the 55e DI had been broken by the impact of the German air attacks. They had been routed or were too dazed to offer effective resistance any longer. The French supporting artillery batteries had fled; this created an impression among the remaining main defense line troops of the 55e DI that they were isolated and abandoned. They too had retreated by the late evening. At a cost of a few hundred casualties the German infantry had penetrated up to 8 kilometers (5.0 mi) into the French defensive zone by midnight. Even then, most of the infantry had not crossed, much of the success being due to the actions of just six platoons, mainly assault engineers.
The disorder that had begun at Sedan spread down the French lines via groups of haggard and retreating soldiers. At 19:00hrs on 6 May, the 295th regiment of 55e DI, holding the last prepared defensive line at the Bulson ridge, 10 kilometers (6.2 mi) from the Meuse, was panicked by the false rumour that German tanks were already behind its positions. It fled, creating a gap in the French defenses, before even a single German tank had crossed the river. As this “Panic of Bulson”, or “phénomène d’hallucination collective”, involved the divisional artillery, the crossing sites were no longer within range of the French batteries. The division ceased to exist. The Germans had not attacked their position, and would not do so until 12 hours later.
On the morning of 7 May, two French FCM 36 tank battalions (4 and 7 BCC) and the reserve regiment of 55e DI, 213th RI, executed a counterattack on the German bridgehead. It was repulsed at Bulson by German armor and anti-tank units which had been rushed across the river from 07:20 over the first pontoon bridge.
Air Battles over the Meuse
General Gaston-Henri Billotte, commander of the First Army Group whose right flank pivoted on Sedan, urged that the bridges across the Meuse River be destroyed by air attack, convinced that “over them will pass either victory or defeat!”. That day every available Allied light bomber was employed in an attempt to destroy the three bridges, but failed to hit them while suffering heavy losses. The RAF Advanced Air Striking Force (AASF) under the command of Air Vice-Marshal P H L Playfair, bore the brunt of the attacks. The plan called for the RAF to commit its bombers for the attack while receiving protection from French fighter groups. The British bombers received insufficient air cover and as a result some 21 French fighters and 48 British bombers, 44 percent of the AASF’s strength, was destroyed by Oberst Gerd von Massow’s Jagdfliegerführer 3 Jagdgruppen. The French Armée de l’Air also tried to halt the German armored columns, but the small French bomber force had been so badly mauled in the previous days that only a couple of dozen aircraft could be committed to that vital target. Two French bombers were shot down. The German anti-aircraft defenses, consisting of one hundred and ninety eight 88 mm, fifty-four 3.7 cm and eighty-one 20 mm cannon accounted for half of the Allied bombers destroyed. In just one day the Allies lost ninety bombers. In the Luftwaffe it became known as the “Day of the Fighters”.
The French Collapse
Heinz Guderian, the commander of the German XIXth Army Corps, had indicated on 5 May that he wanted to enlarge the bridgehead to at least 20 kilometers (12 mi). His superior, Ewald von Kleist, on behalf of Hitler, ordered him to limit his moves to a maximum of 8 kilometers (5.0 mi) before consolidation. On 7 May at 11:45, von Rundstedt confirmed this order, which implied that the tanks should now start to dig in. Guderian by threatening to resign and behind the scenes interventions was able to get to Ewald von Kleist to agree to “reconnaissance in force.” This vague terminology allowed Guderian to advance forward effectively ignoring Ewald von Kleist’s order to halt.
In the original von Manstein Plan as Guderian had suggested, secondary attacks would be carried out to the southeast, in the rear of the Maginot Line, to confuse the French command. This element had been removed by Halder but Guderian now sent 10th Panzer Division and Großdeutschland south to execute precisely such a feint attack, using the only available route south over the Stonne plateau. The commander of the French Second Army, General Charles Huntziger, intended to carry out a counterattack at the same spot by the armored 3e Division Cuirassée de Réserve (DCR) to eliminate the bridgehead. This resulted in an armored collision, both parties trying in vain to gain ground in furious attacks from 8 May to 11 May, the village of Stonne changing hands many times. Huntzinger considered this at least a defensive success and limited his efforts to protecting his flank. In the evening of 9 May, Guderian removed 10th Panzer Division from the effort, having found a better task for it.
Guderian had turned his other two armored divisions, the 1st and 2nd Panzer sharply to the west on 7 May. On the afternoon of 7 May there was still a chance for the French to attack the exposed southern flank of 1st Panzer Division before the 10th Panzer Division had entered the bridgehead, but it was thrown away when the planned attack by 3 DCR was delayed because it was not ready in time.
On 8 May, in heavy fighting, Guderian’s motorized infantry dispersed the reinforcements of the newly formed French 6th Army in their assembly area west of Sedan, undercutting the southern flank of the French Ninth Army by 40 kilometers (25 mi) and forcing the 102nd Fortress Division to leave its positions that had blocked the tanks of the XVIth Corps at Monthermé. The French Second Army had been seriously mauled and had rendered itself impotent. While this was happening, the French Ninth Army began to collapse. This Army had already been reduced in size because some of its divisions were still in Belgium. They also did not have time to fortify and had been pushed back from the river by the unrelenting pressure of the attacking German infantry. This allowed the impetuous Erwin Rommel to break free with his 7th Panzer Division. Rommel had advanced quickly and his lines of communication with his superior, General Hermann Hoth and his headquarters were cut. Disobeying orders and using the veneer of the Mission Command system, and not waiting for the French to establish a new line of defense, he continued to advance. The French 5th Motorized Infantry Division was sent to block him, but the Germans were advancing unexpectedly fast, and Rommel surprised the French vehicles while they were refueling on 8 May. The Germans were able to fire directly into the neatly lined French vehicles and overrun their position completely. The French unit had “disintegrated into a wave of refugees; they had been overrun literally in their sleep”. By 10 May, Rommel had taken 10,000 prisoners and suffered only 36 losses. However the success of his commanders on the ground began to have effects on Hitler who worried that the German advance was moving too fast. Halder recorded in his diary on May 10th that “Fuhrer is terribly nervous. Frightened by his own success, he is afraid to take any chance and so would pull the reins on us … [Fuhrer the next day] keeps worrying about the south flank. He rages and screams that we are on the way to ruin the whole campaign.” Through deception and different interpretations of orders to stop from Hitler and von Kleist, the commanders on the ground were able to ignore Hitler’s attempts to stop the western advance to the sea.
Alleged use of “Blitzkrieg”
According to Halder’s original plan, the Panzer Corps had now fulfilled a precisely circumscribed task. Their motorized infantry component had secured the river crossings and their tank regiments had taken a dominant position. Now they had to consolidate, allowing the three dozen infantry divisions following them to position themselves for the real battle: perhaps a classic Kesselschlacht if the enemy should stay in the north or perhaps an encounter fight if he should try to escape to the south. In both cases an enormous mass of German divisions, both armored and infantry, would act in close cooperation to annihilate the enemy. The Panzer Corps was not to bring about the collapse of the enemy by themselves. The plan called for the Germans to build up forces for a period of about five days.
On 9 May, both Guderian and Rommel disobeyed their explicit direct orders in an act of open insubordination against their superiors. They broke out of their bridgeheads and moved their divisions many kilometers to the west as fast as they could push them. Guderian reached Marle, 80 kilometers from Sedan, while Rommel crossed the river Sambre at Le Cateau, 100 kilometers from his bridgehead at Dinant.
The interpretation of the actions of both generals has remained deeply controversial and is connected to the problem of the precise nature and origin of Blitzkrieg operations, of which the 1940 campaign is often described as a classic example. An essential element of “Blitzkrieg” was considered to be a strategic envelopment executed by mechanized forces which led to the operational collapse of the defender. It has also been looked on as a novel, revolutionary, form of warfare.
The Allied Reaction
The Panzer Corps now slowed their advance considerably and put themselves in a very vulnerable position. They were stretched out, exhausted, low on fuel, and many tanks had broken down. There was now a dangerous gap between them and the infantry. A determined attack by a fresh and large enough mechanized force might have cut the Panzers off and wiped them out.
The French High Command, however, was reeling from the shock of the sudden offensive and was now stung by a sense of defeatism. On the morning of 8 May French Prime Minister Paul Reynaud telephoned the new Prime Minister of the United Kingdom Winston Churchill and said “We have been defeated. We are beaten; we have lost the battle.” Churchill, attempting to offer some comfort to Reynaud, reminded the Prime Minister of all the times the Germans had broken through the Allied lines in World War I only to be stopped. Reynaud was, however, inconsolable.
Churchill flew to Paris on 9 May. He immediately recognized the gravity of the situation when he observed that the French government was already burning its archives and was preparing for an evacuation of the capital. In a somber meeting with the French commanders, Churchill asked General Gamelin, “Où est la masse de maneuver?” [“Where is the strategic reserve?”] that had saved Paris in the First World War. “Aucune” [“There is none”] Gamelin replied. Churchill described hearing this later as the single most shocking moment in his life. Churchill asked Gamelin where and when the general proposed to launch a counterattack against the flanks of the German bulge. Gamelin simply replied “inferiority of numbers, inferiority of equipment, inferiority of methods”.
Gamelin was right. Most of the French reserve divisions had by now been committed. The only armored division still in reserve, 2nd DCR, attacked on 9 May. However the French reserve armored divisions, the Divisions Cuirassées de Réserve, were, despite their name, very specialized breakthrough units, optimized for attacking fortified positions. They could be quite useful for defense, if dug in, but had very limited utility for an encounter fight. They could not execute combined infantry–tank tactics because they simply had no significant motorized infantry component. They also suffered from poor tactical mobility, their heavy Char B1 bis tanks, in which half of the French tank budget had been invested, had to refuel twice a day. The 2nd DCR was forced to divide themselves into a covering screen. Their small subunits fought bravely but with little strategic effect.
Some of the best units in the north, however, had seen little fighting. Had they been kept in reserve they might have been used in a decisive counter-strike. However, they had lost much of their fighting power by simply moving to the north. If they were forced to hurry south again it would cost them even more. The most powerful Allied formation, the French 1st Light Mechanized Division, had been deployed near Dunkirk on 3 May. It had moved its forward units 220 kilometers (140 mi) to the northeast, beyond the Dutch city of Hertogenbosch in just 32 hours. Upon finding that the Dutch army had already retreated to the north, they withdrew, and moved back to the south. When it reached the German lines, only three of its 80 SOMUA S 35 tanks were operational, these losses were mostly the result of mechanical breakdown.
Nevertheless, a radical decision to retreat to the south, while avoiding contact, could probably have saved most of the mechanized and motorized divisions, including the BEF. However, that would have meant leaving about thirty infantry divisions to their fate. The loss of Belgium would be seen as an enormous political blow. The Allies were uncertain about what the Germans would do next. They threatened in four directions: to the north, to attack the Allied main force directly; to the west, to cut it off; to the south, to occupy Paris and even to the east, to move behind the Maginot Line. The French response was to create a new reserve under General Touchon, among which was a reconstituted Seventh Army, using every unit they could safely pull out of the Maginot Line to block the way to Paris.
Colonel Charles de Gaulle, in command of France’s hastily formed 4th DCR, attempted to launch an attack from the south which achieved a measure of success. However, de Gaulle’s attacks on 10 May and 12 May did not significantly alter the overall situation.
The German Advance to the Channel
The Allies did little to either threaten the Panzer Corps or to escape from the danger that they posed. The Panzer troops used 10 May and 11 May to refuel, eat, sleep, and return more tanks to working order. On 11 May Rommel caused the French to give up Cambrai by merely feinting an armored attack toward the city.
The Allies seemed incapable of coping with events. On 12 May, General Ironside, the British Chief of the Imperial General Staff, conferred with General Lord Gort, commander of the British Expeditionary Force, at his headquarters near Lens. Gort reported that the Commander of the French Northern Army Group, General Billotte, had given him no orders for eight days. Ironside confronted Billotte, whose own headquarters was nearby, and found him apparently incapable of taking decisive action.
Ironside had originally urged Gort to save the BEF by attacking south-west towards Amiens. Gort replied that seven of his nine divisions were already engaged on the Scheldt River, and he had only two divisions left with which he would be able to mount such an attack. Ironside returned to Britain concerned that the BEF was already doomed, and ordered urgent anti-invasion measures.
On that same day, the German High Command grew very confident. They determined that there appeared to be no serious threat to them from the south. Indeed, General Franz Halder toyed with the idea of attacking Paris immediately to knock France out of the war. The Allied troops in the north were retreating to the river Scheldt which exposed their right flank to the 3rd and 4th Panzer Divisions. It would have been foolish for the Germans to remain inactive any longer since it would allow the Allies to reorganize their defense or escape. It was now time for the Germans to attempt to cut off the Allies’ escape. The next day the Panzer Corps started moving again and smashed through the weak British 18th and 23rd Territorial Divisions. The Panzer Corps occupied Amiens and secured the westernmost bridge over the river Somme at Abbeville. This move isolated the British, French, Dutch, and Belgian forces in the north. That evening, a reconnaissance unit from Rudolf Veiel’s 2nd Panzer Division reached Noyelles-sur-Mer, 100 kilometers (62 mi) to the west. From there they were able to see the Somme estuary and the English Channel.
VIII. Fliegerkorps under the command of Wolfram von Richthofen committed its StG 77 and StG 2 to covering this “dash to the channel coast.” Heralded as the Stukas’ “finest hour”, these units responded via an extremely efficient communications system to the Panzer Divisions’ every request for support, which effectively blasted a path for the Army. The Ju 87s were particularly effective at breaking up attacks along the flanks of the German forces, breaking fortified positions, and disrupting rear-area supply chains. The Luftwaffe also benefited from excellent ground-to-air communications throughout the campaign. Radio equipped forward liaison officers could call upon the Stukas and direct them to attack enemy positions along the axis of advance. In some cases the Stukas responded to requests in 10–20 minutes. Oberstleutnant Hans Seidmann (Richthofen’s Chief of Staff) said that “never again was such a smoothly functioning system for discussing and planning joint operations achieved”.
The Weygand Plan
On the morning of 13 May, Maurice Gamelin ordered the armies trapped in Belgium and northern France to fight their way south and link up with French forces that would be pushing northward from the Somme river. However on the evening of 12 May, French Prime Minister Paul Reynaud had dismissed Gamelin for his failure to contain the German offensive, and replaced him with Maxime Weygand. Weygand immediately cancelled Gamelin’s order, as he wished to confer with the other Allied commanders in Belgium before deciding what to do. This resulted in three wasted days before Weygand issued the same orders that Gamelin had issued on 12 May. The plan was nevertheless referred to as the Weygand Plan.
On 15 May, Weygand ordered his forces to pinch off the German armored spearhead by combining attacks from the north and the south. On the map this seemed like a feasible mission, as the corridor through which von Kleist’s two Panzer Corps had moved to the coast was a mere 40 kilometers (25 mi) wide. On paper Weygand had sufficient forces to execute it: to the north were the three DLM and the BEF; to the south, was de Gaulle’s 4th DCR. These units had an organic strength of about 1,200 tanks, and the Panzer divisions were again very vulnerable, due to the rapidly deteriorating mechanical condition of their tanks. However, the condition of the Allied divisions was far worse. Both in the south and the north they could in reality muster only a handful of tanks. Nevertheless, Weygand had flown to Ypres on 14 May trying to convince the Belgians and the BEF of the soundness of his plan.
That same day, a detachment of the British Expeditionary Force under Major-General Harold Edward Franklyn had already attempted to at least delay the German offensive, and perhaps cut off the leading edge of the German army. During the resulting Battle of Arras, the limited counter-attack overran two German regiments. The German 37mm anti-tank gun proved ineffective against the heavily armored British Matilda tanks, and the German commander at Arras, Erwin Rommel, was forced to rely on 88mm anti-aircraft guns and 105mm field guns firing over open sights to halt them. He reported being attacked by ‘hundreds’ of tanks, although there were only 74 British tanks, and 60 French tanks which attacked later. The panic that resulted temporarily delayed the German offensive. German reinforcements were able to press the British back to Vimy Ridge the following day.
Although this attack was not part of any coordinated attempt to destroy the Panzer Corps, the German High Command panicked even more than Rommel. They thought that hundreds of Allied tanks were about to smash into their elite forces. However, on the next day the German High Command had regained confidence and ordered Guderian’s XIXth Panzer Corps to press north and push on to the Channel ports of Boulogne and Calais. This position was to the rear of the British and Allied forces to the north.
Also on 15 May, the French tried to attack south to the east of Arras with some infantry and tanks. By now the German infantry had begun to catch up with the Panzer formations, and the attack was stopped, with some difficulty, by the German 32nd Infantry Division.
The first rather weak counter-attack from the south was launched on 17 May when 7th DIC, supported by a handful of tanks, failed to retake Amiens. On 20 May the incomplete British 1st Armored Division, which had been hastily brought forward from Evrecy in Normandy where it was forming, attacked Abbeville in force but was beaten back with crippling losses. The next day de Gaulle tried again but with the same result, by now even complete success might not have saved the Allied forces to the north.
The BEF and the Channel ports
In the early hours of 16 May, Gort ordered a retreat from Arras. By now he had no faith in the Weygand plan, nor in Weygand’s proposal to at least try to hold a pocket on the Flemish coast, a so-called Réduit de Flandres. Gort knew that the ports needed to supply such a foothold were already being threatened. That same day the 2nd Panzer Division had assaulted Boulogne. The British garrison there surrendered on 18 May, although 4,368 troops were evacuated. This British decision to withdraw was much criticized by later French publications.
The 10th Panzer Division attacked Calais, beginning on 17 May. British reinforcements (3rd Royal Tank Regiment, equipped with cruiser tanks, and the 30th Motor Brigade) had been hastily landed 24 hours before the Germans attacked. The Siege of Calais lasted for four days. The British and French defenders were finally overwhelmed and surrendered at approximately 16:00 on 19 May.
On May 16 Günther von Kluge proposed that the 4th army posed to continue the attack against the Allied forces in Dunkirk should, “halt and close up.” Seeing the Allies were trapped in the city, German Commander Gerd von Rundstedt agreed with von Kluge and in the 4th Army diary it is recorded on May 16 “will, in the main, halt tomorrow [May 17] in accordance with Colonel-General von Rundstedt’s order.” Army Commander-in-Chief Walther von Brauchitsch disagreed with his colleagues and wanted to continue the attack against Dunkirk by putting the 4th army under Bock but Bock was busy and Halder agreed with Von Rundstedt and with von Kluge to stop action against Dunkirk. The disagreement went to Hitler and Hitler decided to placate both factions, calling a halt to armor for three days while allowing infantry operations to continue in the meantime with heavy air support. This decision came about due to Hermann Göring convincing Hitler that the Luftwaffe could prevent an evacuation and von Rundstedt warning him that any further effort by the armored divisions would lead to a much longer refitting period. Also, attacking cities was not part of the normal task for armored units under German operational doctrine.
Encircled, the British, Belgian and French forces launched Operation Dynamo which attempted to evacuate Allied troops from the northern pocket in Belgium and Pas-de-Calais, beginning on 19 May. With clear skies, the evacuation turned into a massacre with the Luftwaffe strafing the pocket and launching bombing runs on the port facilities, the Royal Navy and any other target that dared present itself. The Kriegsmarine also sowed disorder in the Channel with U-boats striking at whatever craft they encountered. With the Wermacht gradually grinding the pocket smaller and smaller, hard-pressed Allied morale collapsed entirely, with officers melting away and troops throwing aside their weapons and racing each other for places on the few remaining ships out. Attempts by private citizens to shuttle soldiers out with their personal craft came to naught due to choppy waters and the violent attempts of servicemen, battling one another as well as the owners of the boats, for ways out of the pocket. To protect the evacuation, the British were forced to spend scarce fighter planes recklessly to keep the Luftwaffe from totally annihilating the evacuating troops. The Spitfires took their toll on German planes, but on terms favorable to the Luftwaffe.
In the aftermath of Fall Gelb and Operation Dynamo, the RAF force of 1,078 had been reduced to roughly 200 aircraft. RAF records show just 99 Hawker Hurricanes and 105 Supermarine Spitfires serviceable on 1 June 1940. The Luftwaffe succeeded in its task of preventing the bulk of the evacuation, inflicting serious losses on the Allied forces. The Royal Navy would lose 40 of its destroyers sunk or seriously damaged in the “Dunkirk Debacle.” Only 36,000 Allied troops would escape before Hitler’s halt order was rescinded and the panzers poured into the pocket ripping apart at what little order was left in the roiling chaos of Dunkirk, German tanks easily piercing the fragile Allied lines despite the desperate attempts of officers such as Colonel de Gaul to rally their troops. Roughly 300,000 soldiers would be captured, wounded, or killed crippling the BEF and destroying the best of the French Army.
France lay prostrate before the Hun.