A major center of trade and culture on the Silk Road, Bukhara has a documented history extending back for two and a half millenia. During its Golden Age under the Sunni Persian Samanid Emirate in the ninth and tenth centuries, Bukhara was a center of Islamic civilization rivaling Baghdad. The autonomous Bukharan Emirate was conquered by the Red Army in 1920 and subsequently incorporated into the Uzbekistan Soviet Socialist Republic. The local population is partly ethnic Tajik and largely Takjik speaking; the long established Bukharan Jewish community has now mostly emigrated to Israel. The historic center of Bukhara, filled with splendid monuments of Islamic architecture constructed over the course of several hundred years, is now a UNESCO World Heritage Site. These monuments, some of which are seen here, comprise mosques, madrassas, minarets, a walled fortress, mausoleums and a necropolis.