World War II
From Halopedia, the Halo wiki
World War II was probably the second most brutal war in the history of mankind before the Interplanetary War. World War II was fought between the Allied Nations and the Axis Alliance (led by Chancellor Adolf Hitler) and lasted six years, from 1939 - 1945. The war was won by the Allied Nations and shortly afterwards, the victors of the war formed the United Nations organization, which would later form the United Nations Space Command.