Husayn ibn Ali, a grandson of Muhammad, was killed at the Battle of Karbala (depicted) by the forces of Yazid I, whom Husayn had refused to recognize as caliph. Battle of Karbala: The Battle of Karbala was fought on 10 October 680 between the forces of the second Umayyad caliph Yazid I, and a small army led by Husayn ibn Ali, second son of Ali and grandson of the Islamic prophet Muhammad, at Karbala, in modern-day southern Iraq. October 10, 680. Wiki link