Trebizond Vilayet
The Vilayet of Trebizond or Trabzon was a first-level administrative division (vilayet) in the north-eastern part of the Ottoman Empire and corresponding to the area along the eastern Black Sea coastline and the interior highland region of the Pontic Alps. The region was populated mainly by ethnic Turks in the western half and Laz-speaking Muslims in the eastern half, although throughout the period of Ottoman rule there was a history of conversion to Turkish Islam of many of the region's Pontic Greeks - with even Gulbahar Hatun, the mother of sultan Selim the Grim said to be of Pontic Greek origin.
At the beginning of the 20th century it reportedly had an area of 12,082 square miles (31,290 km2), while the preliminary results of the first Ottoman census of 1885 (published in 1908) gave the population as 1,047,700. The accuracy of the population figures ranges from "approximate" to "merely conjectural" depending on the region from which they were gathered.
After the Russian-Turkish War of 1877-1878, the sanjak of Lazistan was established.Rize became the center of the district due to the cession of Batumi, the former centre of the sanjak, to Russia.