In the 1948 Palestine war, more than 700,000 Palestinian Arabs – about half of Mandatory Palestine's predominantly Arab population – were expelled or fled from their homes, at first by Zionist paramilitaries, and after the establishment of Israel, by its military. The expulsion and flight was a central component of the fracturing, dispossession, and displacement of Palestinian society, known as the Nakba. Dozens of massacres targeting Arabs were conducted by Israeli military forces and between 400 and 600 Palestinian villages were destroyed. Village wells were poisoned in a biological warfare programme and properties were looted to prevent Palestinian refugees from returning. Other sites were subject to Hebraization of Palestinian place names.
The precise number of Palestinian refugees, many of whom settled in Palestinian refugee camps in neighboring states, is a matter of dispute, although the number is around 700,000, being approximately 80 percent of the Arab inhabitants of what became Israel. About 250,000–300,000 Palestinians fled or were expelled during the 1947–1948 civil war in Mandatory Palestine, before the termination of the British Mandate on 14 May 1948. The desire to prevent the collapse of the Palestinians and to avoid more refugees were some of the reasons for the entry of the Arab League into the country, which began the 1948 Arab–Israeli War.