Husayn ibn Ali
Husayn ibn Ali (11 or 13 January 626 CE – 13 October 680 CE) was the third Imam of Shia Islam. He was the son of Ali ibn Abi Talib, the fourth Caliph and first Imam of Shia Islam. His mother was Fatimah Zahra, the daughter of the Prophet Muhammad and wife of Ali. He was also the younger brother of Hasan ibn Ali, the second Imam of Shia Islam.
Husayn ibn Ali is known as a great figure in Shia Islam. He refused to submit to Yazid I, the Umayyad caliph. For this he was killed at the Battle of Karbala, along with most of his family. He is regarded as a martyr by Shia Muslims and his Grandson mahdi will Vengeance from his Killers.