German invasion of France in 1940
The Battle of France (; 10 May – 25 June 1940), also known as the Western Campaign (German: "Westfeldzug"), the French Campaign (, ) and the Fall of France, during the Second World War was the German invasion of the Low Countries (Belgium, Luxembourg and the Netherlands) and France. The invasion plan for the Low Countries and France was called Fall Gelb (). Fall Rot () was planned to finish off the French and British after the evacuation at Dunkirk. The Low Countries and France were defeated and occupied by Axis troops down to the Demarcation line. In November 1942, Wehrmacht troops also occupied Vichy France ending land operations on the Western Front until the Normandy landings began on 6 June 1944.
On 3 September 1939, France and Britain declared war on Nazi Germany, over the German invasion of Poland on 1 September. In early September 1939, France began the limited Saar Offensive but by mid-October had withdrawn to their start lines. Starting 10 May 1940, Wehrmacht armies invaded Belgium, Luxembourg, the Netherlands, and parts of France.
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 where 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 ("Case Red") on 5 June 1940. The remaining Allied divisions in France, sixty French and two British, made a determined stand on the Somme and Aisne rivers but were defeated by the German combination of air superiority and armoured mobility. Italy entered the war on the German side on 10 June 1940 and began the Italian invasion of France. 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.
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 (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.
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Background.
Maginot Line.
During the 1930s, the French built the Maginot Line, fortifications along the border with Germany. 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. 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. 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.
German invasion of Poland.
In 1939, the United Kingdom and France offered military support to Poland in the likely case of a German invasion. 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. 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.
Phoney War.
On 7 September, in accordance with the Franco-Polish alliance, France began the Saar Offensive with an advance from the Maginot Line 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 , joke war or the German , 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, in a speech to the Reichstag he made a peace offer to the Western powers.
German strategy.
(Case Yellow).
On 9 October 1939, Hitler issued 6 (). 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. 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. 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. 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.
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 (Deployment Instruction No. 1, Case Yellow). Colonel-General Franz Halder (Chief of the General Staff [OKH]), presented the first plan for on 19 October. entailed an advance through the middle of Belgium; 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. 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.
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 , with a secondary attack on the Netherlands. 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. 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.
Halder's plan satisfied no-one; General Gerd von Rundstedt, the commander of Army Group A () recognised that it did not adhere to the classic principles of (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, 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.
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. 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).
Such a risky independent use of armour had been widely discussed in Germany before the war but OKH doubted such an operation could work. 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. 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. 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.
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