As part of the anti-British course, it was deemed necessary by Hitler to have Poland either a satellite state or otherwise neutralized. Hitler believed this necessary both on strategic grounds as a way of securing theReich's eastern flank and on economic grounds as a way of evading the effects of a British blockade. Initially, the German hope was to transform Poland into a satellite state, but by March 1939 the German demands had been rejected by the Poles three times, which led Hitler to decide upon the destruction of Poland as the main German foreign policy goal of 1939. On 3 April 1939, Hitler ordered the military to start preparing for Fall Weis (Case White), the plan for a German invasion to be executed on 25 August 1939. In August 1939, Hitler spoke to his generals that his original plan for 1939 had to "... establish an acceptable relationship with Poland in order to fight against the West" but since the Poles would not co-operate in setting up an "acceptable relationship" (i.e. becoming a German satellite), he believed he had no choice other than wiping Poland off the map. The historian Gerhard Weinberg has argued since Hitler's audience comprised men who were all for the destruction of Poland (anti-Polish feelings were traditionally very strong in the German Army), but rather less happy about the prospect of war with Britain and France, if that was the price Germany had to pay for the destruction of Poland, it is quite likely that Hitler was speaking the truth on this occasion. In his private discussions with his officials in 1939, Hitler always described Britain as the main enemy that had to be defeated, and in his view, Poland's obliteration was the necessary prelude to that goal by securing the eastern flank and helpfully adding to Germany's Lebensraum. Hitler was much offended by the British "guarantee" of Polish independence issued on 31 March 1939, and told his associates that "I shall brew them a devil's drink". In a speech in Wilhelmshaven for the launch of the battleship Tirpitz on 1 April 1939, Hitler threatened to denounce the Anglo-German Naval Agreement if the British persisted with their "encirclement" policy as represented by the "guarantee" of Polish independence. As part of the new course, in a speech before the Reichstag on 28 April 1939, Adolf Hitler, complaining of British "encirclement" of Germany, renounced both the Anglo-German Naval Agreement and the German–Polish Non-Aggression Pact.
As a pretext for aggression against Poland, Hitler claimed the Free City of Danzig and the right for "extra-territorial" roads across the Polish Corridor which Germany had unwillingly ceded under the Versailles treaty. For Hitler, Danzig was just a pretext for aggression as the Sudetenland had been intended to be in 1938, and throughout 1939, while highlighting the Danzig issue as a grievance, the Germans always refused to engage in talks about the matter. A notable contradiction existed in Hitler's plans between the long-term anti-British course, whose major instruments such as a vastly expanded Kriegsmarine and Luftwaffe would take several years to complete, and Hitler's immediate foreign policy in 1939, which was likely to provoke a general war by engaging in such actions as attacking Poland. Hitler's dilemma between his short-term and long-term goals was resolved by Foreign Minister Joachim von Ribbentrop, who told Hitler that neither Britain nor France would honour their commitments to Poland, and any German–Polish war would accordingly be a limited regional war. Ribbentrop based his appraisal partly on an alleged statement made to him by the French Foreign Minister Georges Bonnet in December 1938 that France now recognized Eastern Europe as Germany's exclusive sphere of influence. In addition, Ribbentrop's status as the former Ambassador to London made him in Hitler's eyes the leading Nazi British expert, and as a result, Ribbentrop's advice that Britain would not honour her commitments to Poland carried much weight with Hitler. Ribbentrop only showed Hitler diplomatic cables that supported his analysis. In addition, the German Ambassador in London, Herbert von Dirksen, tended to send reports that supported Ribbentrop's analysis such as a dispatch in August 1939 that reported British Prime Minister Neville Chamberlain knew "the social structure of Britain, even the conception of the British Empire, would not survive the chaos of even a victorious war", and so would back down. The extent that Hitler was influenced by Ribbentrop's advice can be seen in Hitler's orders to the German military on 21 August 1939 for a limited mobilization against Poland alone. Hitler chose late August as his date for Fall Weiss in order to limit disruption to German agricultural production caused by mobilization. The problems caused by the need to begin a campaign in Poland in late August or early September in order to have the campaign finished before the October rains arrived, and the need to have sufficient time to concentrate German troops on the Polish border left Hitler in a self-imposed situation in August 1939 where Soviet co-operation was absolutely crucial if he were to have a war that year.
The Munich agreement appeared to be sufficient to dispel most of the remaining hold which the "collective security" idea may have had in Soviet circles, and, on 23 August 1939, Joseph Stalin accepted Hitler's proposal to conclude a non-aggression pact (the Molotov-Ribbentrop Pact), whose secret protocols contained an agreement to partition Poland. A major historical debate about the reasons for Hitler's foreign policy choices in 1939 concerns whether a structural economic crisis drove Hitler into a "flight into war" as claimed by the Marxist historian Timothy Mason or whether Hitler's actions were more influenced by non-economic factors as claimed by the economic historian Richard Overy. Historians such as William Carr, Gerhard Weinberg and Ian Kershaw have argued that a non-economic reason for Hitler's rush to war was Hitler's morbid and obsessive fear of an early death, and hence his feeling that he did not have long to accomplish his work. In the last days of peace, Hitler oscillated between the determination to fight the Western powers if he had to, and various schemes intended to keep Britain out of the war, but in any case, Hitler was not to be deterred from his aim of invading Poland. Only very briefly, when news of the Anglo-Polish alliance being signed on 25 August 1939 in response to the German-Soviet Non-Aggression Pact (instead of the severing of ties between London and Warsaw predicted by Ribbentrop) together with news from Italy that Mussolini would not honour the Pact of Steel, caused Hitler to postpone the attack on Poland from 25 August to 1 September Hitler chose to spend the last days of peace either trying to manoeuvre the British into neutrality through his offer of 25 August 1939 to "guarantee" the British Empire, or having Ribbentrop present a last-minute peace plan to Henderson with an impossibly short time limit for its acceptance as part of an effort to blame the war on the British and Poles. On 1 September 1939, Germany invaded western Poland. Britain and France declared war on Germany on 3 September but did not immediately act. Hitler was most unpleasantly surprised at receiving the British declaration of war on 3 September 1939, and turning to Ribbentrop angrily asked "Now what?" Ribbentrop had nothing to say other than that Robert Coulondre, the French Ambassador, would probably be by later that day to present the French declaration of war. Not long after this, on 17 September, Soviet forces invaded eastern Poland.
|“||Poland never will rise again in the form of the Versailles treaty. That is guaranteed not only by Germany, but also ... Russia.||”|
- – Adolf Hitler in a public speech in Danzig at the end of September 1939.
After the fall of Poland came a period journalists called the "Phoney War," or Sitzkrieg ("sitting war"). In part of north-western Poland annexed to Germany, Hitler instructed the twoGauleiters in charge of the area, namely Albert Forster and Arthur Greiser, to "Germanize" the area, and promised them "There would be no questions asked" about how this "Germanization" was to be accomplished. Hitler's orders were interpreted in very different ways by Forster and Greiser. Forster followed a policy of simply having the local Poles sign forms stating they had German blood with no documentation required, whereas Greiser carried out a brutal ethnic cleansing campaign of expelling the entire Polish population into the Government-General of Poland. When Greiser, seconded by Himmler, complained to Hitler that Forster was allowing thousands of Poles to be accepted as "racial" Germans and thus "contaminating" German "racial purity", and asked Hitler to order Forster to stop, Hitler merely told Himmler and Greiser to take up their difficulties with Forster, and not to involve him. Hitler's handling of the Forster–Greiser dispute has often been advanced as an example of Ian Kershaw's theory of "Working Towards the Führer", namely that Hitler issued vague instructions, and allowed his subordinates to work out policy on their own.
After the conquest of Poland, another major dispute broke out between different factions with one centring around Reichsfüherer SS Heinrich Himmler and Arthur Greiserchampioning and carrying out ethnic cleansing schemes for Poland, and another centring around Hermann Göring and Hans Frank calling for turning Poland into the "granary" of the Reich. At a conference held at Göring's Karinhall estate on 12 February 1940, the dispute was settled in favour of the Göring-Frank view of economic exploitation, and ending mass expulsions as economically disruptive. On 15 May 1940, Himmler showed Hitler a memo entitled "Some Thoughts on the Treatment of Alien Population in the East", which called for expelling the entire Jewish population of Europe into Africa and reducing the remainder of the Polish population to a "leaderless labouring class". Hitler called Himmler's memo "good and correct". Hitler's remark had the effect of scuttling the so-called Karinhall argreement, and led to the Himmler–Greiser viewpoint triumphing as German policy for Poland.
During this period, Hitler built up his forces on Germany's western frontier. In April 1940, German forces invaded Denmark and Norway. In May 1940, Hitler's forces attacked France, conquering Luxembourg, the Netherlands and Belgium in the process. These victories persuaded Benito Mussolini of Italy to join the war on Hitler's side on 10 June 1940. France surrendered on 22 June 1940.
Britain, whose forces evacuated France by sea from Dunkirk, continued to fight alongside other British dominions in the Battle of the Atlantic. After having his overtures for peace rejected by the British, now led by Winston Churchill, Hitler ordered bombing raids on the United Kingdom. The Battle of Britain was Hitler's prelude to a planned invasion. The attacks began by pounding Royal Air Force airbases and radar stations protecting South-East England. However, the Luftwaffe failed to defeat the Royal Air Force. On 27 September 1940, the Tripartite Pact was signed in Berlin by Saburō Kurusu of Imperial Japan, Hitler, and Ciano. The purpose of the pact, which was directed against an unnamed power that was clearly meant to be the United States, was to deter the Americans from supporting the British. It was later expanded to include Hungary, Romania and Bulgaria. They were collectively known as the Axis powers. By the end of October 1940, air superiority for the invasion Operation Sea Lion could not be assured, and Hitler ordered the bombing of British cities, including London, Plymouth, and Coventry, mostly at night.
In the Spring of 1941, Hitler was distracted from his plans for the East by various activities in North Africa, the Balkans, and the Middle East. In February, German forces arrived in Libya to bolster the Italian forces there. In April, he launched the invasion of Yugoslavia which was followed quickly by the invasion of Greece. In May, German forces were sent to support Iraqi rebel forces fighting against the British and to invade Crete. On 23 May, Hitler released Führer Directive No. 30.