Germany invades Belgium and Britain declares war on Germany.
July 28: Outbreak of World War I following the assassination of Archduke Franz Ferdinand of Austria by a Serbian nationalist.
Japan declares war on Germany.
The United States enters World War I on the side of the Allies.
The Bolshevik Revolution occurs in Russia, led by Vladimir Lenin and the Communist Party.
Armistice signed between the Allies and Germany, ending World War I.
Benito Mussolini becomes Prime Minister of Italy and establishes the fascist regime.
The Wall Street Crash marks the beginning of the Great Depression in the United States.
Adolf Hitler becomes Chancellor of Germany and begins the Nazi regime.
Franklin D. Roosevelt is inaugurated as President of the United States and implements the New Deal to combat the Great Depression.
Outbreak of the Spanish Civil War between the Republicans (supported by the Soviet Union) and Nationalists (supported by Nazi Germany and Fascist Italy).
Japan signs the Anti-Comintern Pact with Nazi Germany, aimed at countering the spread of communism.
Anschluss occurs as Germany annexes Austria.
Munich Agreement is signed, allowing Germany to annex the Sudetenland region of Czechoslovakia.
Nazi Germany and the Soviet Union sign the Molotov-Ribbentrop Pact, agreeing to divide Eastern Europe between them.
Germany invades Poland, marking the beginning of World War II.
Britain and France declare war on Germany.
Germany launches Operation Barbarossa, invading the Soviet Union. December 7: Japan launches a surprise attack on Pearl Harbor, bringing the United States into World War II.
Tehran Conference is held between the leaders of the Allied powers (Britain, the United States, and the Soviet Union) to plan the strategy for defeating Nazi Germany.
