Battle of Karbala: Martyrdom of Husayn ibn Ali

On October 10, 680 CE, Husayn ibn Ali, grandson of Prophet Muhammad and third Shia imam, was killed with approximately 72 companions by Umayyad Caliph Yazid I's army at Karbala in present-day Iraq. Husayn had refused to pledge allegiance to Yazid, considering him illegitimate. Outnumbered and denied water for three days, Husayn chose death over surrender. The event solidified Shia Islam as a distinct tradition from Sunni Islam. Shia Muslims commemorate the event annually through Ashura mourning rituals, and it has influenced Islamic political theology and resistance movements for fourteen centuries.