The abolition of the Ottoman Sultanate by the Grand National Assembly of Turkey (GNAT) on 1 November 1922 ended the Ottoman Empire, which had lasted since 1299. On 11 November 1922, at the Conference of Lausanne, the sovereignty of the GNAT exercised by the Government in Ankara over Turkey was recognized. The last sultan, Mehmed VI, departed the Ottoman capital, Constantinople, on 17 November 1922. The legal position was solidified with the signing of Treaty of Lausanne on 24 July 1923.
The Ottoman entry into World War I along the Central Powers occurred on 11 November 1914. The Middle Eastern theatre of World War I ended with the signing of the Armistice of Mudros on 30 October 1918. The Occupation of Constantinople by British, French and Italian forces occurred on 13 November 1918.
The partitioning of the Ottoman Empire began with the Treaty of London (1915) and continued with multiple agreements, mostly unilateral among the Allies. British troops began to occupy the key buildings of the Empire and arrest nationalists after the establishment of military rule on the night of 15 March 1920. On 18 March 1920 the Ottoman parliament met and sent a protest to the Allies that it was unacceptable to arrest five of its members. That was the last meeting of the body and marked the end of the Ottoman political system. Sultan Mehmed VI dissolved the General Assembly of the Ottoman Empire on 11 April 1920. The Constantinople government, with the bureaucracy, but without the parliament, was left active with the Sultan as the decision maker.