Mehmed V Reshad (2 November 1844 – 3 July 1918) was the 35th Sultan of the Ottoman Empire, reigning 1909-1918. He also served as the Caliph of Islam. Mehmed personally wielded very little actual authority in his country. His reign coincided with World War I, which his country entered on the side of the Central Powers. It is also during his reign that the Armenian genocide began.
Mehmed died months before the war ended, and he did not live to see his empire's collapse.
Some speculation is necessary, as "the Sultan" is not named in the text. The fact that Abdul Majid II is confirmed to be Sultan in The Center Cannot Hold suggests that his historical predecessor, Mehmed V, held the throne.