How did the Arab conquests of the 7th century change central and southern Iraq?

The Arab conquests of the 7th century fundamentally transformed central and southern Iraq, shifting it from a Sasanian province to the heart of the Muslim Caliphate.1

Key changes included:

• New Urban Centers: Rather than settling throughout the country, Arab arrivals established two major garrison cities: Kūfah, near ancient Babylon, and Basra in the south. These served as bases for fighting men who lived off taxes paid by the local population.1
• Demographic and Social Shifts: The conquest triggered mass immigration of Arabs from eastern Arabia and Oman. While the local population was generally permitted to retain their property and religion, the Persian elite and Zoroastrian priests faced property confiscation.1
• Political Status: Iraq became a subordinate province of the Caliphate, though it remained the wealthiest region with the largest Muslim population. This status led to significant political discontent and rebellion against Umayyad rule, eventually resulting in the establishment of Wāṣit as a base for a permanent Syrian garrison to maintain control.1
• Religious Significance: The region became central to Shiʿi history following the Battle of Karbala in 680, with Karbala and Najaf emerging as vital centers of pilgrimage.1