Diyarbakir (dēyärˈbäkŭrˌ) [key], anc. Amida, city (1990 pop. 375,767), capital of Diyarbakir prov., SE Turkey, on the Tigris (Dicle) River. It is the trade center for a region producing grains, melons, cotton, copper ore, and petroleum. Manufactures of the city include flour, wine, textiles, and machinery. A Roman colony from A.D. 230, the city was taken (mid-4th cent.) by Shapur II of Persia. It was conquered by the Arabs in 638 and later was held by the Seljuk Turks and Persians. The Ottoman Turks captured Diyarbakir in 1515. It is a Kurdish population center. The city retains the magnificent black basalt fortification walls mainly constructed by Constantine I in the 4th cent. Diyarbakir Univ. is there.