A Jewish defence force in Palestine. It was established in 1920 first as an independent, armed organization and then under the control of the Histadrut to defend Jewish settlements. During the 1936–39 Arab rebellion it was considerably expanded. It gained a general staff and was put under control of the Jewish Agency, acquiring new duties of organizing illegal Jewish immigration and preparing for the fight against Britain, who held the mandate over Palestine. In 1941 the Palmah (assault platoons) were formed. In 1948 Haganah provided the nucleus of the Israeli Defence Force, formed to protect the newly created state of Israel.