The 7th century is the period from 601 (DCI) through 700 (DCC) in accordance with the Julian calendar in the Common Era. The spread of Islam and the Muslim conquests began with the unification of Arabia by Prophet Muhammad starting in 622. After Muhammad's death in 632, Islam expanded beyond the Arabian Peninsula under the Rashidun Caliphate (632–661) and the Umayyad Caliphate (661–750). The Muslim conquest of Persia in the 7th century led to the downfall of the Sasanian Empire. Also conquered during the 7th century were Syria, Palestine, Armenia, Egypt, and North Africa.