The devastation of the Great War (as World War I was known at the time) had greatly destabilized Europe, and in many respects World War II grew out of issues left unresolved by that earlier conflict. In particular, political and economic instability in Germany, and lingering resentment over the harsh terms imposed by the Versailles Treaty, fueled the rise to power of Adolf Hitler and National Socialist German Workers' Party, abbreviated as NSDAP in German and the Nazi Party in English..

Did you know? As early as 1923, in his memoir and propaganda tract "Mein Kampf" (My Struggle), Adolf Hitler had predicted a general European war that would result in "the extermination of the Jewish race in Germany."

After becoming Chancellor of Germany in 1933, Hitler swiftly consolidated power, anointing himself Führer (supreme leader) in 1934. Obsessed with the idea of the superiority of the "pure" German race, which he called "Aryan," Hitler believed that war was the only way to gain the necessary "Lebensraum," or living space, for the German race to expand. In the mid-1930s, he secretly began the rearmament of Germany, a violation of the Versailles Treaty. After signing alliances with Italy and Japan against the Soviet Union, Hitler sent troops to occupy Austria in 1938 and the following year annexed Czechoslovakia. Hitler's open aggression went unchecked, as the United States and Soviet Union were concentrated on internal politics at the time, and neither France nor Britain (the two other nations most devastated by the Great War) were eager for confrontation.