The Vilayet of Erzurum (Armenian: Էրզրումի նահանգ, Ottoman Turkish: ولايت ارضروم, Vilâyet-i Erzurum)[2] was a first-level administrative division (vilayet) of the Ottoman Empire.

At the beginning of the 20th century, Erzurum Vilayet reportedly had an area of 29,614 square miles (76,700 km2), while the preliminary results of the first Ottoman census of 1885 (published in 1908) gave the population as 645,702.

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

[4] In 1875 it was divided in six vilayets: Erzurum, Van, Hakkari, Bitlis, Hozat (Dersim) and Kars-Çildir.

In 1888 by an imperial order Hakkari was joined to the vilayet of Van, and Hozat to Mamuret ul-Aziz.