The British Mandate of Palestine was the legal governing power, or authority, granted to Great Britain by the newly created League of Nations, right after World War I, to rule a chunk of Middle East territory, which included today’s Israel and Palestine. Until 1919, this territory was part of the Ottoman (Turkish) Empire, which had allied with Germany and Austro-Hungary to fight against Russia, the United Kingdom, and France. Since the Central Powers lost the war, their empires got dissolved, losing huge pieces of their territories. The Turkish Empire territorial extensions located south of Syria and Lebanon was given over to be administered by the United Kingdom under the League of Nations’ mandate. Although the British troops had already conquered that portion of the Ottoman Empire in 1918, at the end of the Great War, the mandate was formally granted in 1922.
The British Mandate of Palestine lasted until 1947, when the United Nation General Assembly passed Resolution 181, which established the creation of two independent States, a Palestininean and a Jewish States, dividing the British Mandate territory in two halves. According to this resolution, the Jewish legally founded a new nation in the Middle East, declaring their independence in 1948. The coming into being of the modern State of Israel was strongly opposed by the Arab nations, which immediately attempted to destroy it by attacking Israel from all sides in a war that took place from 1948 to 1949.