— Ch. 1 · Origins And Pre-War Alliances —
Allies of World War II.
~9 min read · Ch. 1 of 7
On the 1st of September 1939, Germany invaded Poland and the world shifted into a state of total war. The League of Nations had been established after World War I to prevent such conflicts through collective security. Four major powers from that earlier era, the United Kingdom, France, Italy, and Japan, became permanent members of its council. Yet the system failed when the United States refused to join. Japan withdrew from the League in February 1933 after it criticized Japan's invasion of Manchuria. Nazi Germany followed suit in October 1933, leaving disarmament talks behind.
France tried to protect itself by forming alliances with Poland in 1921 and Czechoslovakia in 1924. The Locarno treaties of 1925 saw Britain, France, Belgium, Germany, and Italy guarantee borders between Germany and its neighbors. But the system crumbled as aggression grew unchecked. In May 1935, France signed a mutual defense agreement with the Soviet Union, which Germany viewed as hostile. When Italy invaded Abyssinia in October 1935, the League imposed only weak sanctions that lasted briefly.
Germany remilitarized the Rhineland in March 1936 without facing any consequences. Britain promised aid to France and Belgium if they were attacked, but no concrete action followed. By July 1937, Japan had begun an undeclared war in China. The League called for sanctions but achieved nothing. Italy joined the Anti-Comintern pact with Germany and Japan in November 1937 before leaving the League entirely.
The crisis deepened when Germany annexed Austria in March 1938. Britain and France protested but took no further steps. They pressured Czechoslovakia to negotiate with Hitler under the Munich Agreement on the 30th of September 1938. That deal ceded the Sudetenland to Germany against Czech wishes. Germany violated it by invading the rest of Czechoslovakia on the 15th of March 1939. Britain and France then pledged to defend Poland if attacked. On the 23rd of August, Germany and the Soviet Union signed a non-aggression pact containing secret protocols dividing Eastern Europe.