Al-Ḥusayn b. ʿAlī b. Abī Ṭālib (a) (b. Sha'ban 3, 4/January 11, 626 – d. Muharram 10, 61/October 10, 680) was known by the Kunya of Abu 'Abd Allah and also known as Imam al-Husayn (a). He is the third Imam of the Shi'a, the martyr of Karbala, one of the People of Kisa' [Cloak], the second son of Imam 'Ali (a) and Lady Fatima (a), and the grandson of the Prophet (s). The Prophet (s) introduced him and his brother, Imam al-Hasan (a), as the Masters of the Youth of Paradise. Imam al-Husayn (a) participated in the battles of Siffin, Jamal and Nahrawan alongside his father.
He obliged to the treaty between his brother and Mu'awiya during its validity. However, after Mu'awiya died, Imam al-Husayn (a) refused to give allegiance to Yazid and considered his rise to caliphate as illegitimate. When Walid b. 'Utba, the governor of Medina, was sent to order Imam al-Husayn (a) to either pledge allegiance to Yazid or be killed, Imam al-Husayn (a) made his way from Medina towards Mecca on Rajab 28, 60/May 7, 680. At the same time, the people of Kufa pledged their support to the Imam (a) as a ruler. As the Imam (a) and his companions made their way to Kufa, the army of 'Ubayd Allah b. Ziyad stopped the Imam's caravan on Yazid's order. For fear of retribution from Yazid's army, the people of Kufa broke their promise of support for the Imam (a). The battle of Karbala took place on the Day of 'Ashura'. Imam (a) along with his few companions (around 72) were martyred and the remaining companions were taken as prisoners to Kufa and Syria.
The martyrdom of Imam al-Husayn (a) was decisive in shaping Islamic and Shi'a history. The timing of the Imam's (a) life and martyrdom were crucial as they were in one of the most challenging periods of the 7th century. During this time, Umayyad oppression was rampant, and the stand the Imam (a) and his followers took became a symbol of resistance inspiring future uprisings against oppressors during that time and future generations to come.