The 1948 Palestine war was fought in the territory of what had been, at the start of the war, British-ruled Mandatory Palestine. During the war, Zionist forces conquered territory and established the State of Israel, over 700,000 Palestinians fled or were expelled from Palestine, the British withdrew from their Mandate of Palestine, and four neighbouring Arab nations entered the territory and joined the war. By the end of the war, the State of Israel had held or captured about 78% of former territory of the mandate, the Kingdom of Jordan had captured and later annexed the area that became the West Bank, and Egypt had captured the Gaza Strip. The war formally ended with the 1949 Armistice Agreements, which established the State of Israel and laid out the Green Line demarcating these territories. It was the first war of the IsraeliāPalestinian conflict and the broader ArabāIsraeli conflict.
The war had two main phases, the first being the 1947ā1948 civil war, which began on 30 November 1947, a day after the United Nations voted to adopt the Partition Plan for Palestine, which planned for the division of the territory into Jewish and Arab sovereign states. During this period, the British still maintained a declining rule over Palestine and occasionally intervened in the violence. Initially on the defensive, the Zionist forces switched to the offensive in April 1948. In anticipation of an invasion by Arab armies, they enacted Plan Dalet, an operation aimed at securing territory for the establishment of a Jewish state.