that the province of Khorasan revolted against Sasanian rule, just as it had years earlier when the population had sided with Khosrau II's uncle Vistahm. When Yazdegerd was crowned in Estakhr, Persia had in fact three Kings ruling in different regions and Khorasan had not initially given support to Yazdegerd. Before Yazdegerd had a chance to receive help from the Hepthalites and Turkish tribes, he was assassinated by a local miller in Merv in 651. Thereafter, Yazdegerd's son Peroz attempted to re-establish the Sasanian empire against the Rashidun Caliphate and its successor, the Umayyad Caliphate, though the plan did not develop, as Peroz ultimately died in China. Impact On the long-term impact of this battle, Sir Muhammad Iqbal wrote: "If you ask me what is the most important event in the history of Islam, I shall say without any hesitation: “The Conquest of Persia.” The battle of Nehawand gave the Arabs not only a beautiful country, but also an ancient civilization; or, more properly, a people who could make a new civilisation with the Semitic and Aryan material. Our Muslim civilisation is a product of the cross-fertilization of the Semitic and the Aryan ideas. It is a child who inherits the softness and refinement of his Aryan mother, and the sterling character of his Semitic father. But for the conquest of Persia, the civilisation of Islam would have been one-sided. The conquest of Persia gave us what the conquest of Greece gave to the Romans." References Sources Battles involving the Sasanian Empire Battles involving the Rashidun Caliphate Muslim conquest of Persia 640s in the Rashidun Caliphate 640s in the Sasanian Empire History of Hamadan Province