1939 - Major Point of Divergence
In 1939 the Nazi-Soviet pact was signed between Stalin and Hitler. In this timeline, Stalin allowed Hitler to take the whole of Poland, without only some small Russian gains made. Stalin also guaranteed Russia's non-involvement in the European War, and a supply of oil for German tanks.
1939 - 1953: The War
Hitler's invasion of Poland and the rest of Europe went much as planned, with Britain soon the last non-allied or neutral country in Europe by 1945. Without American supplies coming in as guaranteed by the 1941 treaty of Non-Aggression between Germany and America, Britain began to starve. However, under a great agricultural program implemented by Winston Churchill Britain managed to produce enough of its own food to survive, and the siege continued. By 1951, however, Germany's hold on mainland Europe was increasingly hard to sustain with large resistance movements arising, and the USA had cancelled its treaty with Germany as part of its war with Japan, and was now shipping food to Britain, though not openly fighting Germany. In May, the siege was deemed to expensive and cancelled, and all hope of conquering Britain faded. Meanwhile, Mussolini had been overthrown and Italy was under control of a firmly anti-German government. Though not declaring war, Italy freed Yugoslavia and Albania who fought the German allies in Eastern Europe successfully, gaining territory and breaking Hitler's alliances with Romania, Hungary and Bulgaria. France and Poland revolted constantly, weakening Germany. In early 1952, the new republican Government in Spain declared war on Germany along with Italy, and British troops landed in Belgium shortly after. Germany's Empire collapsed in late 1953, with the devastating Kaufmann plan being implemented.