In the early 1920s, the League of Nations granted Britain authority over Palestine after World War I and the Ottoman Empire's collapse. This era, known as the British Mandate of Palestine, covered what is now Israel, the West Bank, and Gaza Strip. Tensions between Jewish immigrants and Arab residents were exacerbated by the 1917 Balfour Declaration, in which Britain expressed support for a "national home for the Jewish people" in Palestine.
In 1947, the UN proposed a partition plan for Palestine, accepted by Jews but rejected by Arabs. This led to conflicts and the declaration of the State of Israel on May 14, 1948, marking the end of the British Mandate. This significant moment reshaped the region's history, and the subsequent Arab-Israeli conflicts continue to impact the Middle East's geopolitics.