“Then God raised up against them the sons of Ishmael, [numerous] as the sand on the sea shore, whose leader was Muhammad. Neither walls nor gates, armour or shield, withstood them, and they gained control over the entire land of the Persians.
And Yazdegerd, who was from the royal lineage, was crowned king in the city of Estakhr, and under him, the Persian Empire came to an end. And he went forth and came to Mahoze and appointed one named Rustam as the leader of the army.
Yazdgird sent against them countless troops, but the Arabs routed them all and even killed Rustam.” - the Chronicle of Khuzestan, 7th century