The history of Nishapur begins with the city's founding during the Sasanian dynasty (and given the title of New Shapur); the city is located in the eastern province of Khorasan and served as the seat of the governor and commander in chief of the province. Nishapur retained its importance under the Seljuqs, after its occupation by the first sultan of the Turkic dynasty in 1037. It was sacked by the Oghuz in 1154, and damaged in a series of earthquakes in the twelfth and thirteenth centuries, yet it remained an active urban centre until its destruction by the Mongols in 1221.