650s

650s refers to the decade spanning 650 to 659 CE in the Julian calendar. It sits within the early medieval period when the Rashidun Caliphate expanded and then faced intense internal political challenges as it governed a rapidly growing but diverse empire.

A defining development of the decade was the collapse of the Sassanian Empire. By 651, following the death of Yazdgerd III, large parts of Iran, Mesopotamia, and surrounding regions came under Arab rule, marking a major realignment in the Middle East and the completion of Muslim conquests in the former Sassanian heartland. The conquests continued to motivate military and administrative efforts across newly acquired territories, while existing provincial governance paths were tested by rapid expansion.

The latter part of the decade was dominated by internal conflict within the Muslim community. Uthman ibn Affan was assassinated in 656, triggering a civil strife that brought Ali ibn Abi Talib to the caliphate (656–661). The period saw significant battles, most notably the Battle of the Camel in 656 and the Battle of Siffin in 657, pitting Ali against Muawiyah I. The Khawarij emerged as a radical faction opposing both leaders, and the Battle of Nahrawan (658) highlighted the depth of factionalism. The decade culminated in a shift in power dynamics that would lead to the rise of the Umayyad Caliphate, as Muawiyah consolidated power in the Syrian province and the supplanting of Ali after his death in 661.

Overall, the 650s were a pivotal decade of imperial consolidation and significant internal upheaval that shaped the course of Islamic governance in the subsequent era.