The following day, the armies of four Arab countries—Egypt, Syria, Transjordan and Iraq—entered what had been British Mandatory Palestine, launching the 1948 Arab–Israeli War; Contingents from Yemen, Morocco, Saudi Arabia and Sudan joined the war. The apparent purpose of the invasion was to prevent the establishment of the Jewish state at inception, and some Arab leaders talked about driving the Jews into the sea. According to Benny Morris, Jews felt that the invading Arab armies aimed to slaughter the Jews. The Arab league stated that the invasion was to restore law and order and to prevent further bloodshed.

What four Arab countries entered British Mandatory Palestine?