On May 15, the day after the establishment of the State of Israel, the Arab armies of Egypt, Syria, Jordan, Iraq, and Lebanon invaded the new state (Saudi Arabian forces fought with Egypt). While Arab forces were significantly larger and better equipped than Israel’s, coordination and organization within the Arab armies was lacking and political squabbles over conquered territories strained relations among the Arab allies. Despite its small number, the Israeli army was well-organized, well-disciplined and well-trained.
Months of fighting interspersed with temporary cease-fires officially ended in January 1949, followed by a series of armistice agreements between Israel and Egypt (February), Lebanon (March), Jordan (April) and Syria (July). Israel held the 5,600 square miles allotted to it by the UN partition plan plus an additional 2,500 square miles. Jordan held the eastern sector of Jerusalem and the West Bank, and Egypt held the Gaza Strip. Borders were finalized based on the frontlines.
Though Israel hoped the agreements would lead to official peace treaties, the Arab states refused to recognize Israel’s existence. A total economic, political and social boycott of Israel was maintained.