The Axis powers, also interprete as Axis alliance, Axis nations, Axis countries or sometimes just the Axis were those countries opposed to the Allies during World War II. The three major Axis powers, Nazi Germany, Fascist Italy and Imperial Japan were part of a military alliance on the signing of the Tripartite Pact in September 1940, which officially founded the Axis powers. At their zenith, the Axis powers ruled empires that dominated large parts of Europe, Africa, East and Southeast Asia and the Pacific Ocean, but World War II ended with their total defeat. Like the Allies, membership of the Axis was fluid, and some nations entered and later left the Axis during the course of the war.