Nishapur, meaning New Shapur, was founded during the Sasanian dynasty. Archaeologists and historians disagree about the Sassanid Empire and Shapur I's role in developing Nishapur. The city is located in Iran, 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 center until its destruction by the Mongols in 1221.
After the husband of Genghis Khan's daughter, Taghachar, was killed at Nishapur in 1221 by a Nishapur Muslim border guard, Taghachar ordered the death of all in the city—1.7 million were killed, and the skulls of men, women, and children were piled in pyramids by the Mongols.