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In doing so, the Germans beat the Allies to the punch the Allies had been planning an amphibious landing in which they could begin to surround Germany, cutting off her supply of raw materials from Sweden. While the Western Front remained quiet in April 1940, the fighting between the Allies and the Germans began in earnest with the Norwegian Campaign when the Germans launched Operation Weserübung, the German invasion of Denmark and Norway. German efforts to interdict the Allies' trans-Atlantic trade at sea ignited the Battle of the Atlantic.
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The non-belligerent United States contributed to the Western Allies by discounted sales of military equipment and supplies. In their hurry to re-arm, Britain and France had both begun to buy large numbers of weapons from manufacturers in the United States at the outbreak of hostilities, supplementing their own production. The British Royal Air Force dropped propaganda leaflets on Germany and the first Canadian troops stepped ashore in Britain, while Western Europe was in a strange calm for seven months. There were only some local, minor skirmishes.
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At the Maginot Line on the other side of the border, French troops stood facing them, whilst the British Expeditionary Force and other elements of the French Army created a defensive line along the Belgian border. While most of the German Army was fighting against Poland, a much smaller German force manned the Siegfried Line, their fortified defensive line along the French border. The French forces launched a small offensive, the Saar Offensive against Germany in the Saar region but halted their advance and returned. This was also the period in which the United Kingdom and France did not supply significant aid to Poland, despite their pledged alliance. Although the great powers of Europe had declared war on one another, neither side had yet committed to launching a significant attack, and there was relatively little fighting on the ground. The Phoney War was an early phase of World War II marked by a few military operations in Continental Europe in the months following the German invasion of Poland and preceding the Battle of France. The next few months in the war were marked by the Phoney War. In response, Britain and France declared war on Germany on 3 September. On 1 September 1939, World War II began with the German invasion of Poland. The second phase consisted of large-scale ground combat (supported by a massive strategic air war considered to be an additional front), which began in June 1944 with the Allied landings in Normandy and continued until the defeat of Germany in May 1945. The first phase saw the capitulation of Luxembourg, Netherlands, Belgium, and France during May and June 1940 after their defeat in the Low Countries and the northern half of France, and continued into an air war between Germany and Britain that climaxed with the Battle of Britain. The Western Front was marked by two phases of large-scale combat operations. The Western Front's 1944–1945 phase was officially deemed the European Theater by the United States, whereas Italy fell under the Mediterranean Theater along with North Africa. The Italian front is considered a separate but related theater. The Western Front was a military theatre of World War II encompassing Denmark, Norway, Luxembourg, Belgium, the Netherlands, the United Kingdom, France, and Germany. (~70% of Allied troops and casualties were Americans) ~8,000,000 troops (total that served).4,500,000 troops (total as of Victory in Europe Day).Beginning of the Iron Curtain and the Cold War.Liberation of occupied countries in Western and Northern Europe.Fall of Nazi Germany (concurrently with the Eastern Front and Italian Front).
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