In 1867, the "eyalet" of Kurdistan was dissolved and replaced by the Diyarbekir Vilayet, and Jazirat Ibn ʿUmar became the seat of a "kaza" in the "sanjak" of Mardin. The "kaza" was subdivided into nine "nahiyes", and possessed 210 villages. Osman, son of Bedir Khan, seized Jazirat Ibn ʿUmar in 1878 after his escape from captivity at Constantinople using demobilised Kurdish veterans of the Russo-Turkish War of 1877–78, and proclaimed himself as emir. The rebellion endured for eight months until it was quelled by an Ottoman army led by Shevket Bey. The city was visited by the German scholar Eduard Sachau in 1880. In the late 19th century, the French geographer Vital Cuinet recorded in "La Turquie d'Asie" the city's five caravanserais, one-hundred and six shops, ten cafés, and a vaulted bazaar. At the inception of the "Hamidiye" cavalry corps in 1891, Mustafa, "agha" (chief) of the local Miran clan, enrolled and was made a commander with the rank of paşa, hereafter known as Mustafa Paşa. Throughout the 1890s, Mustafa Paşa exploited his position to seize goods from merchants and plunder Christian villages in the district. In 1892, Mustafa Paşa converted a mosque at Jazirat Ibn ʿUmar into a barracks for his soldiers.