The Battle of Nahāvand (also Nihāvand or Nahāwand) (Arabic:معركة نهاوند) Battle of Nahāwand was fought in 642 between Arab Muslims and Sassanid armies. The battle is known to Muslims as the "Victory of Victories." The History of Tabari mentions that Piruzan, the officer serving the Persian King Yazdgerd III had about 100,000 men, versus a Muslim army of about 30,000-100,000. The Persians were outmanoeuvered, trapped in a narrow mountain valley, and lost many men in the ensuing rout. Yazdegerd escaped to the Merv area, but was unable to raise another substantial army. It was a decisive victory for the Rashidun Caliphate and the Persians consequently lost the surrounding cities including Sephahan (renamed Isfahan). The Khan of the Turks later lent him some soldiers, but the soldiers mutinied