Battle of France

Battle of France
Part of the Western Front of the Second World War
Clockwise from top left: Abandoned equipment in northern France German armies march through Paris British soldiers examine a German anti-tank gun Destroyed French armoured vehicle French soldiers on their way to German POW camps German Panzer II make their way through the Ardennes
Date 10 May – 25 June 1940 (1 month, 2 weeks and 1 day) Location Low Countries and France Result Axis victory Territorial changes Vichy France established Parts of France placed under German and Italian military occupation German annexation of Alsace–Lorraine
Belligerents
Germany  Italy (from 10 June)	show  France  Belgium  United Kingdom  Canada  Netherlands  Poland  Czechoslovakia  Luxembourg
Commanders and leaders
Adolf Hitler  Walther von Brauchitsch  Gerd von Rundstedt  Fedor von Bock  Wilhelm von Leeb  Albert Kesselring  Hugo Sperrle  Benito Mussolini  Prince Umberto	Maurice Gamelin[a]  Alphonse Georges[a]  Maxime Weygand[b]  Gaston Billotte †  Georges Blanchard  André-Gaston Prételat  Benoît Besson  René Olry  Leopold III (POW)  Lord Gort  Henri Winkelman (POW)  Émile Speller (POW)  Władysław Sikorski
Units involved
show Axis armies	show Allied armies
Strength
Germany: 141 divisions 7,378 guns[2] 2,445 tanks[2] 5,638 aircraft[3][c] 3,350,000 troops Italians in the Alps 22 divisions 3,000 guns 300,000 troops Total: 3,650,000 troops	Allies: 135 divisions 13,974 guns 3,383–4,071 French tanks[2][4] <2,935 aircraft[3][d] 3,300,000 troops French in the Alps 5 divisions ~150,000 troops Total: 3,450,000 troops
Casualties and losses
Germany: 27,074 killed 111,034 wounded 18,384 missing[5][6][7] 1,129 aircrew killed[8] 1,236 aircraft lost[5][9] 795–822[10] tanks lost[e] German: 179,547 Italian: 6,029–6,040[f] Total: 185,587	73,000 killed 240,000 wounded 15,000 missing[g] 1,756,000 captured 2,233 aircraft lost[23] 1,749 French tanks lost[h] 689 British tanks lost[i] Total: 2,084,000

The Battle of France (French: bataille de France; 10 May – 25 June 1940), also known as the Western Campaign (German: Westfeldzug), the French Campaign (Frankreichfeldzug, campagne de France) and the Fall of France, during the Second World War, was the German invasion of France, that notably introduced tactics that are still used. France and the Low Countries were conquered, ending land operations on the Western Front until the Normandy landings on 6 June 1944.

On 3 September 1939, France declared war on Germany following the German invasion of Poland. In early September 1939, France began the limited Saar Offensive but by mid-October had withdrawn to their start lines. German armies invaded Belgium, Luxembourg, the Netherlands, and France on 10 May 1940.

In Fall Gelb ("Case Yellow"), German armoured units made a surprise push through the Ardennes and then along the Somme valley, cutting off and surrounding the Allied units that had advanced into Belgium to meet the German armies there. British, Belgian and French forces were pushed back to the sea by the Germans; the British and French navies evacuated the encircled elements of the British Expeditionary Force (BEF) and the French and Belgian armies from Dunkirk in Operation Dynamo.

German forces began Fall Rot ("Case Red") on 5 June 1940. The sixty remaining French divisions and the two British divisions in France made a determined stand on the Somme and Aisne rivers but were defeated by the German combination of air superiority and armoured mobility. German armies outflanked the Maginot Line and pushed deep into France, occupying Paris unopposed on 14 June. After the flight of the French government and the collapse of the French Army, German commanders met with French officials on 18 June to negotiate an end to hostilities. Italy entered the war on the German side on 10 June 1940 and attempted an invasion of France.

On 22 June 1940, the Second Armistice at Compiègne was signed by France and Germany. The neutral Vichy government led by Marshal Philippe Pétain replaced the Third Republic and German military occupation began along the French North Sea and Atlantic coasts and their hinterlands. The Italian invasion of France over the Alps took a small amount of ground and after the armistice, Italy occupied a small area in the south-east. The Vichy regime retained the zone libre (free zone) in the south. Following the Allied invasion of French North Africa in November 1942, in Case Anton, the Germans and Italians took control of the zone until France was liberated by the Allies in 1944.

Background[edit]

Maginot Line[edit]

Main article: Maginot Line

During the 1930s, the French built the Maginot Line, fortifications along the border with Germany.^{[25][page needed]} The line was intended to economise on manpower and deter a German invasion across the Franco–German border by diverting it into Belgium, which could then be met by the best divisions of the French Army. The war would take place outside French territory, avoiding the destruction of the First World War.^[26][27] The main section of the Maginot Line ran from the Swiss border and ended at Longwy; the hills and woods of the Ardennes region were thought to cover the area to the north.^[28] General Philippe Pétain declared the Ardennes to be "impenetrable" as long as "special provisions" were taken to destroy an invasion force as it emerged from the Ardennes by a pincer attack. The French commander-in-chief, Maurice Gamelin also believed the area to be safe from attack, noting it "never favoured large operations". French war games, held in 1938, of a hypothetical German armoured attack through the Ardennes, left the army with the impression that the region was still largely impenetrable and that this, along with the obstacle of the Meuse River, would allow the French time to bring up troops into the area to counter any attack.^[29]

German invasion of Poland[edit]

Main article: Invasion of Poland

In 1939, the United Kingdom and France offered military support to Poland in the likely case of a German invasion.^[30] At dawn on 1 September 1939, the German invasion of Poland began. France and the United Kingdom declared war on 3 September, after an ultimatum for German forces immediately to withdraw their forces from Poland was not answered.^[31] Australia and New Zealand also declared war on 3 September, South Africa on 6 September and Canada on 10 September. While British and French commitments to Poland were met politically, the Allies failed to fulfil their military obligations to Poland, later called the Western betrayal by the Poles. The possibility of Soviet assistance to Poland had ended with the Munich Agreement of 1938, after which the Soviet Union and Germany eventually negotiated the Molotov–Ribbentrop Pact, which included an agreement to partition Poland. The Allies settled on a long-war strategy in which they would complete the rearmament plans of the 1930s while fighting a defensive land war against Germany and weakening its war economy with a trade blockade, ready for an eventual invasion of Germany.^[32]

Phoney War[edit]

Main articles: Saar Offensive and Phoney War

On 7 September, in accordance with the Franco-Polish alliance, France began the Saar Offensive with an advance from the Maginot Line 5 km (3 mi) into the Saar. France had mobilised 98 divisions (all but 28 of them reserve or fortress formations) and 2,500 tanks against a German force consisting of 43 divisions (32 of them reserves) and no tanks. The French advanced until they met the thin and undermanned Siegfried Line. On 17 September, Gamelin gave the order to withdraw French troops to their starting positions; the last of them left Germany on 17 September, the day of the Soviet invasion of Poland. Following the Saar Offensive, a period of inaction called the Phoney War (the French Drôle de guerre, joke war or the German Sitzkrieg, sitting war) set in between the belligerents. Adolf Hitler had hoped that France and Britain would acquiesce in the conquest of Poland and quickly make peace. On 6 October, he made a peace offer to both Western powers.^[33][34][35]

German strategy[edit]

Fall Gelb (Case Yellow)[edit]

On 9 October 1939, Hitler issued Führer-Directive Number 6 (Führer-Anweisung N°6).^[33] Hitler recognised the necessity of military campaigns to defeat the Western European nations, preliminary to the conquest of territory in Eastern Europe, to avoid a two-front war but these intentions were absent from Directive N°6.^[36] The plan was based on the seemingly more realistic assumption that German military strength would have to be built up for several years. Only limited objectives could be envisaged and were aimed at improving Germany's ability to survive a long war in the west.^[37] Hitler ordered a conquest of the Low Countries to be executed at the shortest possible notice to forestall the French and prevent Allied air power from threatening the industrial area of the Ruhr.^[38] It would also provide the basis for a long-term air and sea campaign against Britain. There was no mention in the directive of a consecutive attack to conquer the whole of France, although the directive read that as much as possible of the border areas in northern France should be occupied.^[36][39]

On 10 October 1939, Britain refused Hitler's offer of peace and on 12 October, France did the same. The pre-war German codename of plans for a campaign in the Low Countries was Aufmarschanweisung N°1, Fall Gelb (Deployment Instruction No. 1, Case Yellow). Colonel-General Franz Halder (Chief of the General Staff Oberkommando des Heeres (OKH)), presented the first plan for Fall Gelb on 19 October.^[40] Fall Gelb entailed an advance through the middle of Belgium; Aufmarschanweisung N°1 envisioned a frontal attack, at a cost of half million German soldiers to attain the limited goal of throwing the Allies back to the River Somme. German strength in 1940 would then be spent and only in 1942 could the main attack against France begin.^[41] When Hitler raised objections to the plan and wanted an armoured breakthrough, as had happened in the invasion of Poland, Halder and Brauchitsch attempted to dissuade him, arguing that while the fast-moving mechanised tactics were effective against a "shoddy" Eastern European army, they would not work against a first-rate military like the French.^[42]

Hitler was disappointed with Halder's plan and initially reacted by deciding that the Army should attack early, ready or not, hoping that Allied unreadiness might bring about an easy victory. Hitler proposed an invasion on 25 October 1939 but accepted that the date was probably unrealistic. On 29 October, Halder presented Aufmarschanweisung N°2, Fall Gelb, with a secondary attack on the Netherlands.^[43] On 5 November, Hitler informed Walther von Brauchitsch that he intended the invasion to begin on 12 November. Brauchitsch replied that the military had yet to recover from the Polish campaign and offered to resign; this was refused but two days later Hitler postponed the attack, giving poor weather as the reason for the delay.^[44][45] More postponements followed, as commanders persuaded Hitler to delay the attack for a few days or weeks, to remedy some defect in the preparations or to wait for better weather. Hitler also tried to alter the plan, which he found unsatisfactory; his weak understanding of how poorly prepared Germany was for war and how it would cope with losses of armoured vehicles were not fully considered. Though Poland had been quickly defeated, many armoured vehicles had been lost and were hard to replace. This led to the German effort becoming dispersed; the main attack would remain in central Belgium, secondary attacks would be undertaken on the flanks. Hitler made such a suggestion on 11 November, pressing for an early attack on unprepared targets.^[46]

Halder's plan satisfied no-one; General Gerd von Rundstedt, the commander of Army Group A (Heeresgruppe A) recognised that it did not adhere to the classic principles of Bewegungskrieg (war of manoeuvre) that had guided German strategy since the 19th century. A breakthrough was needed to encircle and destroy the main body of Allied forces. The most practical place to achieve this would be in the region of Sedan, which lay in the sector of Army Group A. On 21 October, Rundstedt agreed with his chief of staff, Generalleutnant Erich von Manstein, that an alternative operational plan to reflect these principles was needed, by making Army Group A as strong as possible at the expense of Army Group B to the north.^[47]

Manstein Plan[edit]

Main article: Manstein Plan

While Manstein was formulating new plans in Koblenz, Generalleutnant Heinz Guderian, commander of the XIX Army Corps, was lodged in a nearby hotel.^[48] Manstein was initially considering a move north from Sedan, directly in the rear of the main Allied mobile forces in Belgium. When Guderian was invited to contribute to the plan during informal discussions, he proposed that most of the Panzerwaffe should be concentrated at Sedan. This concentration of armour would advance to the west to the English Channel, without waiting for the main body of infantry divisions. This might lead to a strategic collapse of the enemy, avoiding the relatively high number of casualties normally caused by a Kesselschlacht (cauldron battle).^[49]

Such a risky independent use of armour had been widely discussed in Germany before the war but OKH doubted such an operation could work.^[49] Manstein's general operational ideas won immediate support from Guderian, who understood the terrain, having experienced the conditions with the German Army in 1914 and 1918.^[50] Manstein wrote his first memorandum outlining the alternative plan on 31 October. In it he avoided mentioning Guderian and played down the strategic part of the armoured units, to avoid unnecessary resistance.^[51] Six more memoranda followed between 31 October 1939 and 12 January 1940, each becoming more radical. All were rejected by OKH and nothing of their content reached Hitler.^[50]

Mechelen incident[edit]

Main article: Mechelen incident

On 10 January 1940, a German aircraft, carrying a staff officer with the Luftwaffe plans for an offensive through central Belgium to the North Sea, force-landed near Maasmechelen (Mechelen) in Belgium. The documents were captured but Allied intelligence doubted that they were genuine. In the full moon period in April 1940, another Allied alert was called for a possible attack on the Low Countries or Holland, an offensive through the Low Countries to outflank the Maginot Line from the north, an attack on the Maginot Line or an invasion through Switzerland. None of the contingencies anticipated the German attack through the Ardennes but after the loss of the Luftwaffe plans, the Germans assumed that the Allied appreciation of German intentions would have been reinforced. Aufmarschanweisung N°3, Fall Gelb, an amendment to the plan on 30 January, was only a revision of details. On 24 February, the main German effort was moved south to the Ardennes.^[52] Twenty divisions (including seven panzer and three motorised divisions) were transferred from Heeresgruppe B opposite Holland and Belgium to Heeresgruppe A facing the Ardennes. French military intelligence uncovered a transfer of German divisions from the Saar to the north of the Moselle but failed to detect the redeployment from the Dutch frontier to the Eifel–Moselle area.^[53]

Adoption of the Manstein Plan[edit]

On 27 January, Manstein was sacked as Chief of Staff of Army Group A and appointed commander of an army corps in East Prussia. To silence Manstein, Halder had instigated his transfer to Stettin on 9 February. Manstein's staff brought his case to Hitler, who had independently suggested an attack at Sedan, against the advice of OKH. On 2 February, Hitler was told of Manstein's plan and on 17 February, Hitler summoned Manstein, General Rudolf Schmundt (Chief of Personnel of the German Army) and General Alfred Jodl, the Chief of Operations of Oberkommando der Wehrmacht (OKW, Supreme Command of the Armed Forces), to a conference.^[54] The next day, Hitler ordered Manstein's thinking to be adopted, because it offered the possibility of decisive victory.^[55] Hitler recognised the breakthrough at Sedan only in tactical terms, whereas Manstein saw it as a means to an end. He envisaged an operation to the English Channel and the encirclement of the Allied armies in Belgium; if the plan succeeded, it could have a strategic effect.^[56]

Halder then went through an "astonishing change of opinion", accepting that the Schwerpunkt should be at Sedan. He had no intention of allowing an independent strategic penetration by the seven Panzer divisions of Army Group A. Much to the dismay of Guderian, this element was absent from the new plan, Aufmarschanweisung N°4, Fall Gelb, issued on 24 February.^[43] The bulk of the German officer corps was appalled and called Halder the "gravedigger of the Panzer force". Even when adapted to more conventional methods, the new plan 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 impossible to adequately resupply, along routes that could be cut easily by the French. If the Allies did not react as expected, the German offensive could end in catastrophe. Their objections were ignored and Halder argued that, as Germany's strategic position seemed hopeless anyway, even the slightest chance of decisive victory should be grasped.^[57] Shortly before the invasion, Hitler, who had spoken to forces on the Western Front and who was encouraged by the success in Norway, confidently predicted the campaign would take only six weeks. He was most excited over the planned military glider attack on Fort Eben-Emael.^[58]

Allied strategy[edit]

Escaut Plan/Plan E[edit]

See also: French war planning 1920–1940

On 3 September 1939, French military strategy had been settled, taking in analyses of geography, resources and manpower. The French Army would defend in the east (right flank) and attack on the west (left flank) by advancing into Belgium, to fight forward of the French frontier. The extent of the forward move was dependent on events, which were complicated when Belgium ended the Franco-Belgian Accord of 1920 after the German Remilitarisation of the Rhineland on 7 March 1936. The neutrality of the Belgian state was reluctant openly to co-operate with France but information was communicated about Belgian defences. By May 1940, there had been an exchange of the general nature of French and Belgian defence plans but little co-ordination against a German offensive to the west, through Luxembourg and eastern Belgium. The French expected Germany to breach Belgian neutrality first, providing a pretext for French intervention or that the Belgians would request support when an invasion was imminent. Most of the French mobile forces were assembled along the Belgian border, ready to forestall the Germans.^[59]

An early appeal for help might give the French time to reach the German–Belgian frontier but if not, there were three feasible defensive lines further back. A practicable line existed from Givet to Namur, across the Gembloux Gap (la trouée de Gembloux), Wavre, Louvain and along the Dyle river to Antwerp, which was 70–80 km (43–50 mi) shorter than the alternatives. A second possibility was a line from the French border to Condé, Tournai, along the Escaut (Scheldt) to Ghent and thence to Zeebrugge on the North Sea coast, possibly further along the Scheldt (Escaut) to Antwerp, which became the Escaut Plan/Plan E. The third possibility was along field defences of the French border from Luxembourg to Dunkirk. For the first fortnight of the war, Gamelin favoured Plan E, because of the example of the fast German advances in Poland. Gamelin and the other French commanders doubted that they could move any further forward before the Germans arrived. In late September, Gamelin issued a directive to Général d'armée Gaston Billotte, commander of the 1st Army Group,

...assuring the integrity of the national territory and defending without withdrawing the position of resistance organised along the frontier....

— Gamelin^[60]

giving the 1st Army Group permission to enter Belgium, to deploy along the Escaut according to Plan E. On 24 October, Gamelin directed that an advance beyond the Escaut was only feasible if the French moved fast enough to forestall the Germans.^[61]

Dyle Plan/Plan D[edit]

By late 1939, the Belgians had improved their defences along the Albert Canal and increased the readiness of the army; Gamelin and Grand Quartier Général (GQG) began to consider the possibility of advancing further than the Escaut. By November, GQG had decided that a defence along the Dyle Line was feasible, despite the doubts of General Alphonse Georges, commander of the North-Eastern Front, about reaching the Dyle before the Germans. The British had been lukewarm about an advance into Belgium, but Gamelin persuaded them; on 9 November, the Dyle Plan was adopted. On 17 November, a session of the Supreme War Council deemed it essential to occupy the Dyle Line and Gamelin issued a directive that day detailing a line from Givet to Namur, the Gembloux Gap, Wavre, Louvain and Antwerp. For the next four months, the Dutch and Belgian armies laboured over their defences, the British Expeditionary Force (BEF) expanded and the French army received more equipment and training. Gamelin also considered a move towards Breda in the Netherlands; if the Allies prevented a German occupation of Holland, the ten divisions of the Dutch army would join the Allied armies, control of the North Sea would be enhanced and the Germans would be denied bases for attacks on Britain.^[62]

By May 1940, the 1st Army Group was responsible for the defence of France from the Channel coast south to the Maginot Line. The Seventh Army (Général d'armée Henri Giraud), BEF (General Lord Gort), First Army (Général d'armée Georges Maurice Jean Blanchard) and Ninth Army (Général d'armée André Corap) were ready to advance to the Dyle Line, by pivoting on the right (southern) Second Army. The Seventh Army would take over west of Antwerp, ready to move into Holland and the Belgians were expected to delay a German advance, then retire from the Albert Canal to the Dyle, from Antwerp to Louvain. On the Belgian right, the BEF was to defend about 20 km (12 mi) of the Dyle from Louvain to Wavre with nine divisions and the First Army, on the right of the BEF, was to hold 35 km (22 mi) with ten divisions from Wavre across the Gembloux Gap to Namur. The gap from the Dyle to Namur north of the Sambre, with Maastricht and Mons on either side, had few natural obstacles and was a traditional route of invasion, leading straight to Paris. The Ninth Army would take post south of Namur, along the Meuse to the left (northern) flank of the Second Army.^[63]

The Second Army was the right (eastern) flank army of the 1st Army Group, holding the line from Pont à Bar 6 km (3.7 mi) west of Sedan to Longuyon. GQG considered that the Second and Ninth armies had the easiest task of the army group, dug in on the west bank of the Meuse on ground that was easily defended and behind the Ardennes, a considerable obstacle, the traversing of which would give plenty of warning of a German attack in the centre of the French front. After the transfer from the strategic reserve of the Seventh Army to the 1st Army Group, seven divisions remained behind the Second and Ninth armies and more could be moved from behind the Maginot Line. All but one division were either side of the junction of the two armies, GQG being more concerned about a possible German attack past the north end of the Maginot Line and then south-east through the Stenay Gap, for which the divisions behind the Second Army were well placed.^[64]

Breda variant[edit]

If the Allies could control the Scheldt Estuary, supplies could be transported to Antwerp by ship and contact established with the Dutch Army along the river. On 8 November, Gamelin directed that a German invasion of the Netherlands must not be allowed to progress around the west of Antwerp and gain the south bank of the Scheldt. The left flank of the 1st Army Group was reinforced by the Seventh Army, containing some of the best and most mobile French divisions, which moved from the general reserve by December. The role of the army was to occupy the south bank of the Scheldt and be ready to move into Holland and protect the estuary by holding the north bank along the Beveland Peninsula (now the Walcheren–Zuid-Beveland–Noord-Beveland peninsula) in the Holland Hypothesis.^[65]

On 12 March 1940, Gamelin discounted dissenting opinion at GQG and decided that the Seventh Army would advance as far as Breda, to link with the Dutch. Georges was told that the role of the Seventh Army on the left flank of the Dyle manoeuvre would be linked to it and Georges notified Billotte that if it were ordered to cross into the Netherlands, the left flank of the army group was to advance to Tilburg if possible and certainly to Breda. The Seventh Army was to take post between the Belgians and Dutch by passing the Belgians along the Albert Canal and then turning east, a distance of 175 km (109 mi), when the Germans were only 90 km (56 mi) distant from Breda. On 16 April, Gamelin also made provision for a German invasion of the Netherlands but not Belgium, by changing the deployment area to be reached by the Seventh Army; the Escaut Plan would only be followed if the Germans forestalled the French move into Belgium.^[65]

Allied intelligence[edit]

In the winter of 1939–40, the Belgian consul-general in Cologne had anticipated the angle of advance that Manstein was planning. Through intelligence reports, the Belgians deduced that German forces were concentrating along the Belgian and Luxembourg frontiers. In March 1940, Swiss intelligence detected six or seven Panzer divisions on the German-Luxembourg-Belgian border and more motorised divisions were detected in the area. French intelligence were informed through aerial reconnaissance that the Germans were constructing pontoon bridges about halfway over the Our River on the Luxembourg–German border. On 30 April, the French military attaché in Bern warned that the centre of the German assault would come on the Meuse at Sedan, sometime between 8 and 10 May. These reports had little effect on Gamelin, as did similar reports from neutral sources such as the Vatican and a French sighting of a 100 km-long (60 mi) line of German armoured vehicles on the Luxembourg border trailing back inside Germany.^[66][67]

Prelude[edit]

See also: Order of battle for the Battle of France

German Army[edit]

Germany had mobilised 4,200,000 men of the Heer (German Army), 1,000,000 of the Luftwaffe (German Air Force), 180,000 of the Kriegsmarine (German Navy) and 100,000 of the Waffen-SS (military arm of the Nazi Party). When consideration is made for those in Poland, Denmark and Norway, the Army had 3,000,000 men available for the offensive starting on 10 May 1940. These manpower reserves were formed into 157 divisions. Of these, 135 were earmarked for the offensive, including 42 reserve divisions. The German forces in the west in May and June deployed some 2,439 tanks and 7,378 guns.^[68] In 1939–40, 45 per cent of the army was at least 40 years old and 50 per cent of all the soldiers had just a few weeks' training. The German Army was far from motorised; ten per cent of their army was motorised in 1940 and could muster only 120,000 vehicles, compared with the 300,000 of the French Army. All of the British Expeditionary Force was motorised.^[69] Most of the German logistical transport consisted of horse-drawn vehicles.^[70] Only 50 per cent of the German divisions available in 1940 were fit for operations, often being worse equipped than the German army of 1914 or their equivalents in the British and French Armies. In the spring of 1940, the German Army was semi-modern; a small number of the best-equipped and "elite divisions were offset by many second and third rate divisions".^[71]

Army Group A, commanded by Gerd von Rundstedt, comprised 45+1⁄2 divisions, including seven Panzer and was to execute the main movement effort through the Allied defences in the Ardennes. The manoeuvre carried out by the Germans is sometimes referred to as a "Sichelschnitt", the German translation of the phrase "sickle cut" coined by Winston Churchill after the event. It involved three armies (the 4th, 12th and 16th) and had three Panzer corps. The XV had been allocated to the 4th Army but the XLI (Reinhardt) and the XIX (Guderian) were united with the XIV Army Corps of two motorised infantry divisions on a special independent operational level in Panzergruppe Kleist (XXII Corps).^[72] Army Group B (Fedor von Bock), comprised 29+1⁄2 divisions including three armoured, was to advance through the Low Countries and lure the northern units of the Allied armies into a pocket. It was composed of the 6th and 18th Armies. Army Group C, (General Wilhelm Ritter von Leeb) comprising 18 divisions of the 1st and 7th Armies, was to prevent a flanking movement from the east and with launching small holding attacks against the Maginot Line and the upper Rhine.^[73]

Communications[edit]

Wireless proved essential to German success in the battle. German tanks had radio receivers that allowed them to be directed by platoon command tanks, which had voice communication with other units. Wireless allowed tactical control and far quicker improvisation than the opponent. Some commanders regarded the ability to communicate to be the primary method of combat and radio drills were considered to be more important than gunnery. Radio allowed German commanders to co-ordinate their formations, bringing them together for a mass firepower effect in attack or defence. The French numerical advantage in heavy weapons and equipment, which was often deployed in "penny-packets" (dispersed as individual support weapons) was offset. Most French tanks also lacked radio and orders between infantry units were typically passed by telephone or verbally.^[74]

The German communications system permitted a degree of communication between air and ground forces. Attached to Panzer divisions were the Fliegerleittruppen (Tactical Air Control Party troops) in wheeled vehicles. There were too few Sd.Kfz. 251 command vehicles for all of the army but the theory allowed the army in some circumstances to call Luftwaffe units to support an attack. Fliegerkorps VIII, equipped with Junkers Ju 87 dive-bombers (Stukas), was to support the dash to the Channel if Army Group A broke through the Ardennes and kept a Ju 87 and a fighter group on call. On average, they could arrive to support armoured units within 45–75 minutes of orders being issued.^[75]

Tactics[edit]

The German army conducted combined arms operations of mobile offensive formations, with well-trained artillery, infantry, engineer and tank formations, integrated into Panzer divisions. The elements were united by wireless communication, which enabled them to work together at a quick tempo and exploit opportunities faster than the Allies. Panzer divisions could conduct reconnaissance, advance to contact or defend and attack vital positions and weak spots. Captured ground would be occupied by infantry and artillery as pivot points for further attacks. Although many German tanks were outgunned by their opponents, they could lure Allied tanks onto the divisional anti-tank guns.^[76] The avoidance of tank-versus-tank engagements conserved German tanks for the next stage of the offensive, units carrying supplies for three to four days' operations. The Panzer divisions were supported by motorised and infantry divisions.^[77]

German tank battalions (Panzer-Abteilungen) were to be equipped with the Panzerkampfwagen III and Panzerkampfwagen IV tanks but shortages led to the use of light Panzerkampfwagen II and even lighter Panzerkampfwagen I instead.^{[citation needed]} The German Army lacked a heavy tank like the French Char B1; French tanks were better designs, more numerous, with superior armour and armament but slower and with inferior mechanical reliability than the German designs.^[78][79] Although the German Army was outnumbered in artillery and tanks, it possessed some advantages over its opponents. The newer German Panzers had a crew of five: commander, gunner, loader, driver, and mechanic. Having a trained individual for each task allowed a logical division of labour. French tanks had smaller crews; the commander had to load the main gun, distracting him from observation and tactical deployment.^[74] The Germans enjoyed an advantage through the theory of Auftragstaktik (mission command) by which officers, NCOs and men were expected to use their initiative and had control over supporting arms, rather than the slower, top-down methods of the Allies.^[80]

Luftwaffe[edit]

Army Group B had the support of 1,815 combat, 487 transport aircraft and 50 gliders; 3,286 combat aircraft supported Army Groups A and C. The Luftwaffe was the most experienced, well-equipped and well-trained air force in the world. The combined Allied total was 2,935 aircraft, about half the size of the Luftwaffe.^[81] The Luftwaffe could provide close support with dive-bombers and medium bombers but was a broadly based force, intended to support national strategy and could carry out operational, tactical and strategic bombing operations. Allied air forces were mainly intended for army co-operation but the Luftwaffe could fly air superiority missions, medium-range interdiction, strategic bombing and close air support operations, depending on circumstances. It was not a Panzer spearhead arm, since in 1939 fewer than 15 per cent of Luftwaffe aircraft were designed for close support as this was not its main role.^[82][83]

Flak[edit]

The Germans also had an advantage in anti-aircraft guns (Fliegerabwehrkanone [Flak]). The totals of 2,600 88 mm (3.46 in) heavy Flak guns and 6,700 37 mm (1.46 in) and 20 mm (0.79 in). Light Flak refers to the number of guns in the German armed forces, including the anti-aircraft defence of Germany and the equipment of training units. (A 9,300-gun Flak component with the field army would have needed more troops than the British Expeditionary Force.) The 88 mm Flak had an elevation of −3° to +85° and could therefore be used in a direct fire role, i.e. against panzers.^[84] The armies which invaded the west had 85 heavy and 18 light batteries belonging to the Luftwaffe, 48 companies of light Flak integral to divisions of the army and 20 companies of light Flak allocated as army troops, a reserve in the hands of HQs above corps HQs, altogether about 700 88 mm (3.46 in) and 180 37 mm (1.46 in) guns manned by Luftwaffe ground units and 816 20 mm (0.79 in) guns manned by the army.^[85]

Allies[edit]

France had spent a higher percentage of its GNP from 1918 to 1935 on its military than other great powers^{[example needed]} and the government had added a large rearmament effort in 1936.^{[citation needed]} France mobilised about one-third of the male population between the ages of 20 and 45, bringing the strength of its armed forces to 5,000,000.^[86] Only 2,240,000 of these served in army units in the north. The British contributed a total strength of 897,000 men in 1939, rising to 1,650,000 by June 1940.^{[dubious – discuss]} Dutch and Belgian manpower reserves amounted to 400,000 and 650,000, respectively.^[87]

Armies[edit]

The French Army had 117 divisions, of which 104 (including 11 in reserve) were for the defence of the north. The British contributed 13 divisions in the BEF, three of which were untrained and poorly-armed labour divisions. Twenty-two Belgian, ten Dutch and two Polish divisions were also part of the Allied order of battle. British artillery strength amounted to 1,280 guns, Belgium fielded 1,338 guns, the Dutch 656 guns and France 10,700 guns, giving an Allied total of about 14,000 guns, 45 per cent more than the Germans. The French Army was also more motorised than its opponent, which still relied on horses. Although the Belgians, British and Dutch had few tanks, the French had 3,254, outnumbering the Germans.^[88][89]

Despite several partial mobilisations since 1936, during the full mobilisation in September 1939, officers were unfamiliar with their duties, technical experts were simultaneously expected to hand over their vehicles, report to recruitment centres and were also exempt from service as essential workers. Reservists flooded the depots leading to shortages of beds and poor sanitary conditions. The army lacked 150,000 pairs of trousers, 350,000 blankets, 415,000 tents and 600,000 pairs of boots. Recruits often left their centres and returned home or drank excessively as they waited around for someone to take charge and integrate them. This was a disastrous process not too dissimilar from that of 1870, though the main German blow fell on Poland initially and not France.^[90]

The French mechanised light and heavy armoured divisions (DLM and DCr) were new and not thoroughly trained. Reserve B Divisions were composed of reservists above 30 years old and ill-equipped. A serious qualitative deficiency was a lack of anti-aircraft artillery, mobile anti-tank artillery and wireless, despite the efforts of Gamelin to produce mobile artillery units.^[86][91] Only 0.15 per cent of military spending between 1923 and 1939 had been on radio and other communications equipment; to maintain signals security, Gamelin used telephones and couriers to communicate with field units.^[92]

French tactical deployment and the use of mobile units at the operational level of war was also inferior to that of the Germans.^[86] The French had 3,254 tanks on the north-eastern front on 10 May, against 2,439 German tanks. Much of the armour was distributed for infantry support, each army having a tank brigade (groupement) of about ninety light infantry tanks. With so many tanks available, the French could still concentrate a considerable number of light, medium and heavy tanks in armoured divisions, which in theory were as powerful as German panzer divisions.^[93] Only French heavy tanks generally carried wireless but these were unreliable, hampering communication and making tactical manoeuvre difficult, compared to German units. In 1940, French military theorists still mainly considered tanks as infantry support vehicles and French tanks were slow (except for the SOMUA S35) compared to their German rivals, enabling German tanks to offset their disadvantages by out-manoeuvring French tanks. On several occasions, the French were not able to achieve the same tempo as German armoured units.^[86] The state of training was also unbalanced, with the majority of personnel trained only to man static fortifications. Very little training for mobile action was carried out between September 1939 and May 1940.^[94]

Deployment[edit]

The French Army comprised three army groups; the 2nd and 3rd Army Groups defended the Maginot Line to the east; the 1st Army Group (General Gaston Billotte) was on the western (left) flank, ready to move into the Low Countries. Initially positioned on the left flank near the coast, the Seventh Army, reinforced by a Division Légère Mécanique (DLM, mechanised light division), was intended to move to the Netherlands via Antwerp. To the south of the Seventh Army were the motorised divisions of the BEF, which would advance to the Dyle Line on the right flank of the Belgian army, from Leuven (Louvain) to Wavre. The First Army, reinforced by two DLM and with a Division Cuirassée (DCR, Armoured Division) in reserve, would defend the Gembloux Gap between Wavre and Namur. The southernmost army involved in the move forward into Belgium was the French Ninth Army, which had to cover the Meuse sector between Namur to the north of Sedan.^[26]

Lord Gort, commander of the BEF, expected to have two or three weeks to prepare for the Germans to advance 100 km (60 mi) to the Dyle but the Germans arrived in four days.^[95] The Second Army was expected to form the "hinge" of the movement and remain entrenched. It was to face the elite German armoured divisions in their attack at Sedan. It was given low priority for manpower, anti-aircraft and anti-tank weapons and air support, consisting of five divisions; two were over-age reservist Serie B divisions and the 3rd North African Division.^[96][97] Considering their training and equipment, they had to cover a long front and formed a weak point of the French defence system. GQG had anticipated that the Ardennes Forest would be impassable to tanks, even though Belgian army and French intelligence warned them of long armour and transport columns crossing the Ardennes and being stuck in a huge traffic-jam for some time. French war games in 1937 and 1938 had shown that the Germans could penetrate the Ardennes; Corap called it "idiocy" to think that the enemy could not get through. Gamelin ignored the evidence, as it was not in line with his strategy.^[98]

Air forces[edit]

The Armée de l'Air had 1,562 aircraft, RAF Fighter Command 680 and RAF Bomber Command could contribute about 392 aircraft.^[81] Some Allied types, like the Fairey Battle, were approaching obsolescence. In the fighter force, only the British Hawker Hurricane, the US Curtiss Hawk 75 and the Dewoitine D.520 were a match for the German Messerschmitt Bf 109, the D.520 being more manoeuvrable although being slightly slower.^[99][100] On 10 May 1940, only 36 D.520s had been delivered. The Allies outnumbered the Germans in fighter aircraft, with 81 Belgian, 261 British and 764 French fighters (1,106) against 836 German Bf 109s. The French and British had more aircraft in reserve.^[101]

In early June 1940, the French aviation industry was producing a considerable number of aircraft, with an estimated reserve of nearly 2,000 but a chronic lack of spare parts crippled this fleet. Only about 599 (29 per cent) were serviceable, of which 170 were bombers.^[102] The Germans had six times more medium bombers than the French.^[92][101] Despite its disadvantages, the Armée de l'Air performed far better than expected, destroying 916 enemy aircraft in air-to-air combat, a kill ratio of 2.35:1. Almost a third of the French victories were accomplished by French pilots flying the Curtiss Hawk 75, which accounted for 12.6 per cent of the French single-seat fighter force.^[103]