Axis

The World War II military alliance between Germany, Italy, and Japan, and which later included Japan, Slovakia, Hungary, Romania, Bulgaria, and Finland. The Axis fought against the Allies.

During the 1930s, expansionist aggression on behalf of each of the three principle powers that would form the Axis alliance sowed the seeds of world war: Italy invaded Ethiopia [then Abyssinia], Japan invaded China, and Germany annexed the Sudetenland and Austria.

Increasingly isolated as a result of these acts of aggression, the three nations entered into a series of treaties and pacts with one another. Germany and Italy signed a friendship treaty in October 1936, which became known as the Rome-Berlin Axis. This was followed in November 1936 by the Anti-Comintern Pact between Nazi Germany and Imperial Japan; Italy signed on to the Anti-Comintern Pact a year later. In May 1939, Germany and Italy entered a full military and political alliance with the Pact of Steel.

When World War II broke out following Germany’s attack on Poland on September 1, 1939, Italy initially remained neutral but entered the war on the side of Germany in June 1940, fighting in France as well as against the British in Africa.

The Axis alliance between Germany, Italy, and Japan was formalized when the three powers signed the Tripartite Pact on September 27, 1940. During the war, several other countries joined the Axis, induced by coercion or promises of territory or protection by the Axis powers. They included Hungary, Romania, and Slovakia in November 1940, Bulgaria and Yugoslavia in March 1941, and, after the wartime breakup of Yugoslavia, Croatia. Finland never formally joined the Tripartite Pact but did cooperate with the Axis because of its opposition to the Soviet Union, entering the war against the USSR in 1941.