WRITTEN BY: The Editors of Encyclopaedia Britannica
Balfour Declaration, (November 2, 1917), statement of British support for “the establishment in Palestine of a national home for the Jewish people.” It was made in a letter from Arthur James Balfour, the British foreign secretary, to Lionel Walter Rothschild, 2nd Baron Rothschild (of Tring), a leader of British Jewry. Though the precise meaning of the correspondence has been disputed, its statements were generally contradictory to both the Sykes-Picot Agreement (a secret convention between Britain and France) and the Ḥusayn-McMahon correspondence (an exchange of letters between the British high commissioner in Egypt, Sir Henry McMahon, and Ḥusayn ibn ʿAlī, then emir of Mecca), which in turn contradicted one another (see Palestine, World War I and after).
The Balfour Declaration, issued through the continued efforts of Chaim Weizmann and Nahum Sokolow, Zionist leaders in London, fell short of the expectations of the Zionists, who had asked for the reconstitution of Palestine as “the” Jewish national home. The declaration specifically stipulated that “nothing shall be done which may prejudice the civil and religious rights of existing non-Jewish communities in Palestine.” The document, however, said nothing of the political or national rights of these communities and did not refer to them by name. Nevertheless, the declaration aroused enthusiastic hopes among Zionists and seemed the fulfillment of the aims of the World Zionist Organization (see Zionism).
The British government hoped that the declaration would rally Jewish opinion, especially in the United States, to the side of the Allied powers against the Central Powers during World War I (1914–18). They hoped also that the settlement in Palestine of a pro-British Jewish population might help to protect the approaches to the Suez Canal in neighbouring Egypt and thus ensure a vital communication route to British colonial possessions in India.
The Balfour Declaration was endorsed by the principal Allied powers and was included in the British mandate over Palestine, formally approved by the newly created League of Nations on July 24, 1922. In May 1939 the British government altered its policy in a White Paper recommending a limit of 75,000 further immigrants and an end to immigration by 1944, unless the resident Palestinian Arabs of the region consented to further immigration. Zionists condemned the new policy, accusing Britain of favouring the Arabs. This point was made moot by the outbreak of World War II (1939–45) and the founding of the State of Israel in 1948.
Bibliography : https://www.britannica.com/event/Balfour-Declaration