Hitler-Stalin non-aggression pact – In the Summer of 1939, the UK and France were busily negotiating with Moscow, hopeful of securing a mutual-defense treaty that would halt Hitler. However, on August 23, 1939, a non-aggression treaty was signed between Hitler and Stalin. Now Hitler had the green light to take on the Western world without the threat of a stab in the back by the Soviet Union. Now Hitler ordered the return of areas wrested from Germany after WWI from Poland, and after failing to secure satisfaction, Hitler marched into Poland at dawn on September 1, 1939. Britain and France, honoring their commitment to Poland, promptly declared war on Germany. However, Poland fell in 3 weeks, while Stalin came in on the kill for his share of old Russian Poland. WWII was in full swing. Roosevelt speedily issued the routine proclamations of neutrality, as the US refused to be dragged into a second massive conflict.