Zionism aimed to establish a Jewish homeland in Palestine through political and spiritual renewal. The First Zionist Congress established the international Zionist Organization in 1897. Britain issued the Balfour Declaration in 1917 supporting a Jewish homeland in Palestine and was later given a mandate over Palestine after World War 1. However, Britain's contradictory policies towards Jewish immigration and control of land sales inflamed tensions between Jews and Arabs, culminating in the Arab revolt of 1936-1939. The UN eventually proposed partitioning Palestine in 1947, leading to the establishment of Israel in 1948 and subsequent war with surrounding Arab states.