born с 645, Arabian Peninsula
died 683, Damascus, Syria
Second caliph (680–683) of the Umayyad dynasty .
He oversaw the events at the Battle of Muāwiyah I , as caliph, keeping Muāʽwiyah's advisers and retaining most of his policies, while reforming the financial system, adjusting tax policy, and improving the irrigation system of the Damascus oasis. See also fitnah ; al-{{link=Husayn ibn Ali, al-">Husayn ibn Alī .