Mehmed VI, Ottoman sultan (d. 1926)
Mehmed VI Vahideddin (Ottoman Turkish: محمد سادس Meḥmed-i sâdis or وحيد الدين Vahîdeddin; Turkish: VI. Mehmed or Vahdeddin; 14 January 1861 – 16 May 1926), also known as Şahbaba (lit. 'Emperor-father') among the Osmanoğlu family, was the 36th and last Sultan of the Ottoman Empire, reigning from 4 July 1918 until 1 November 1922, when the Ottoman Empire was dissolved after World War I and replaced by the Republic of Turkey on 29 October 1923.

The brother of Mehmed V, he became heir to the throne in 1916, after the suicide of Abdülaziz's son, Şehzade Yusuf Izzeddin, as the eldest male member of the House of Osman. He acceded to the throne after the death of Mehmed V. He was girded with the Sword of Osman on 4 July 1918 as the thirty-sixth padishah. His father was Sultan Abdulmejid I, and his mother was Gülüstü Hanım (1830–1865). She was an ethnic Abkhaz, the daughter of Prince Tahir Bey Chachba, who was originally named Fatma Chachba.Mehmed stepped down when the Ottoman Sultanate was abolished in 1922 and the secular Republic of Turkey was created, with Mustafa Kemal Atatürk as the first president.