About 72 travellers at Karbala in 680 permanently reshaped Islam
Husayn, the Prophet Muhammad's grandson, refused to swear loyalty to a caliph he considered illegitimate. Setting out for Kufa with roughly 72 companions and family, he was cornered on the plain of Karbala by a far larger Umayyad army and killed. His death cemented the Sunni and Shia split, and the pilgrimage to his shrine is now the largest annual public gathering on earth.
Born in Medina in January 626 to Ali and Fatima, Husayn was a small child when Muhammad died. Tradition records the Prophet carrying him and his elder brother Hasan on his shoulders and calling the pair leaders of the youth of paradise, a hadith preserved in Sunni collections too. The historian Madelung notes some reports hint at a slight preference for Hasan, said to resemble his grandfather more closely.
After Ali's assassination, Hasan handed the caliphate to Mu'awiya under a treaty: Mu'awiya would govern by the Qur'an and Sunnah, a council would pick his successor, and Hasan's followers would be spared. The brothers retreated to Medina for nine years. When Hasan died and the people of Kufa urged revolt, Husayn told them to wait while Mu'awiya lived, honouring the agreement.
Mu'awiya broke it by naming his son Yazid as heir, turning the caliphate into a dynasty. Husayn would not pledge allegiance and in 679 moved to Mecca, where letters poured in from Kufa inviting him to lead them. He sent his cousin Muslim ibn Aqil to test their sincerity and, on a favourable report, set off. A 1,000-strong Umayyad force intercepted his caravan and pushed it north, and on 2 October he camped at Karbala. A second army, estimated at 4,000 to 30,000, arrived, and on 10 October 680 Husayn died there alongside most of his relatives and companions.
The battle gave Ali's supporters a distinct religious identity and helped consolidate Shia Islam. It fed the Second Fitna, including the Tawwabin, or penitents, uprising and later campaigns under Mukhtar al-Thaqafi seeking justice for his death. Muslims widely regard him as a martyr. Each year millions observe ten days of mourning in Muharram, ending on Ashura, and the Arba'in pilgrimage converges on his shrine in Karbala, Iraq.
Source: Husayn ibn Ali
