Yemen Vilayet (Ottoman Turkish: ولايت یمن Vilâyet-i Yemen; Turkish: Yemen Vilayeti) was a first-level administrative division (vilayet) of the Ottoman Empire. At the beginning of the 20th century it reportedly had an area of 200,000 square kilometres (77,200 sq mi). The population for the vilayet is given by the 1885 Ottoman census as 2,500,000, an unreasonably high number for this barren land of deserts which would have been more than the whole population of the far more fertile Ottoman Mesopotamia. Asir formed a sanjak of the vilayet of Yemen.