Ethnic groups in the Bitlis Vilayet based on 1914 population statistics for the Ottoman Empire Bitlis Vilayet (Armenian: Բիթլիսի վիլայեթ Bit'lisi vilayet' , Ottoman Turkish: ولایت بتليس Vilâyet-i Bitlis) was a first-level administrative division (vilayet) of the Ottoman Empire.

Before the Russo-Turkish War (1877–1878) it had been part of the Erzurum Vilayet, it was then made a separate vilayet by the Sublime Porte.

[3] At the beginning of the 20th century, Bitlis Vilayet reportedly had an area of 11,522 square miles (29,840 km2), while the preliminary results of the first Ottoman census of 1885 (published in 1908) gave the population as 388,625.

[4] The accuracy of the population figures ranges from "approximate" to "merely conjectural" depending on the region from which they were gathered.

[4] Bitlis and Muş were formerly included in the Eyalet of Erzurum.