Battle of Nahavand

At Nahavand, near the city of Hamadan in Iran, an Arab Muslim army of the Rashidun Caliphate destroyed the last great field army of the Sasanian Empire in 642. The Muslim commander, al-Nu'man ibn Muqarrin, and his Persian opponent were both killed, but the defeat broke organised Sasanian resistance. It opened the Iranian plateau to the Arab conquest, which in time transformed the religion of the region.

When the Prophet Muhammad died in 632, Islam dominated western Arabia. In the reigns of Abu Bakr and Umar, the first two caliphs, Muslim armies pushed into Palestine and Mesopotamia, confronting both the East Roman and the Persian empires, both of them exhausted by war and internal strife. After defeating the Romans at Yarmouk in 636, the Arabs turned east. In November 636 they beat a Sasanian army at the Battle of al-Qadisiyyah, and the loss of Iraq followed.

The Sasanian king, Yazdegerd III, was forced after a further defeat in 639 to abandon his capital at Ctesiphon and fall back on the Iranian plateau. By 642 he had raised a fresh army in place of the one destroyed at Qadisiyyah.

The Muslim force is estimated at about 30,000 warriors. The Persian army was far larger, with estimates ranging from 50,000 to 150,000, but it was made up largely of farmers and villagers rather than seasoned troops. Many nobles and officials had already deserted Yazdegerd before the battle began, and the Sasanian forces depended on an uneasy alliance of regional magnates.

The sources tell the story in different ways. In one account, the Persians, under a commander called Firuzan, held a strong defensive position until al-Nu'man lured them out with skirmishes followed by an orderly withdrawal. Pursuing in loose order over broken ground and through narrow passes, the Persian horsemen were caught when the Muslims turned and counter-attacked. Another version has the Sasanian army trapped between two mountain defiles and fighting for two days and three nights before it gave way. All versions agree that losses were heavy on both sides, that both commanders died, and that the Persian defeat was complete.

Nahavand marked the near disintegration of the imperial army and the rise of local warlords in Persia. The Sasanians soon lost the surrounding cities, including Isfahan. Yazdegerd fled east and sought help from rulers in Tukharistan and Sogdia, and sent his son Peroz to the Tang court in China, all without success. Several provincial governors received him coldly, and according to some sources the dynasty was unpopular in the east, where Khorasan had rebelled against it. In 651 he was murdered by a miller near Merv. Peroz later tried to restore the dynasty but died in China.

Former Sasanian territories in Tabaristan, south of the Caspian Sea, held out for about a century with the help of Parthian and White Hun nobles, preserving Sasanian court customs, the Zoroastrian faith and the Persian language even as the Umayyad Caliphate replaced the Rashidun. In the longer run, the battle opened the way for the religious transformation of Iran, part of the wider wave of early Muslim conquests that remade the Middle East.

Our 600 map shows the Sasanian Empire a generation before the battle, and our 700 map shows its former lands absorbed into the caliphate that grew out of the Rashidun Caliphate.