During World War I the Assyrians suffered the Assyrian Genocide which reduced their numbers by up to two thirds. Subsequent to this, they entered the war on the side of the British and Russians. After World War I, the Assyrian homeland was divided between the British Mandate of Mesopotamia, which would become the Kingdom of Iraq in 1932, and the French Mandate of Syria which would become the Syrian Arab Republic in 1944.[40][41][42][43]