This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
The Muslim Conquest of Persia was the Rashidun Caliphate's conquest of the Sasanian Empire, beginning with initial raids into Sasanian Iraq in 633 and culminating in the empire's own complete collapse by 651. The decisive engagements were the Battle of al-Qadisiyyah in 636, which broke Sasanian power in Iraq outright and opened the way to the imperial capital Ctesiphon itself, and the Battle of Nahavand in 642, remembered in Islamic tradition as the Victory of Victories for what it achieved.
After Nahavand, organized Sasanian resistance disintegrated into a prolonged campaign across the whole Iranian plateau under Caliphs Umar ibn al-Khattab and later Uthman ibn Affan, against the Sasanian Empire's own last emperor Yazdegerd III, whose royal court fled progressively eastward as each successive province fell to the caliphate's advancing forces, ending nearly four centuries of continuous Sasanian rule over Persia and its many peoples. The distance between al-Qadisiyyah in 636 and the campaign's final conclusion in 651 spanned fifteen years, reflecting the sheer size of the Sasanian Empire the caliphate's forces were dismantling province by province rather than in any single decisive campaign season.