Battle of Karbala
This day is well-known because of mourning for the martyrdom of Husayn ibn Ali, the grandson of Muhammad and the third Shia Imam, along with members of his family and close friends at the Battle of Karbala in the year 61 AH (AD 680). Yazid I was in power then and wanted the Bay'ah (allegiance) of Husayn ibn Ali. Many Muslims believe Yazid was openly going against the teachings of Islam in public and changing the sunnah of Muhammad.
Husayn in his path toward Kufa encountered the army of Ubayd-Allah ibn Ziyad, the governor of Kufa. On October 10, 680 (Muharram 10, 61 AH), he and his small group of companions and family members, who were between 72 and 100 men of Husayn ibn Ali (the grandson of Muhammad). fought with a large army of perhaps more than 100,000 men under the command of Umar ibn Sa'ad, son of the founder of Kufa. Husayn and all of his men were killed. Some of the bodies of the dead, including that of Husayn, were then mutilated.
Commemoration for Husayn ibn Ali began after the Battle of Karbala. After the massacre, the Umayyad army looted Husayn's camp and set off with his women and children for the court of Ibn Ziyad. A moving oration delivered by Zaynab in Kufa is recorded in some sources. The prisoners were next sent to the court of Yazid, Umayyad caliph, in Damascus, where one of his Syrian followers asked for Husayn's daughter Faṭimah al-Kubra, and once again it was Zaynab who came to the rescue and protected her honour. The family remained in Yazid's prison for a time. The first assembly (majlis) of Commemoration of Husayn ibn Ali is said to have been held by Zaynab in prison. In Damascus, too, she is reported to have delivered a poignant oration. The prison sentence ended when Hussain's 4 year old daughter died in captivity, a young girl who would stand at the window of the prison and tell the ladies who would gather outside about the tragedy that befell her family. Her death caused an uproar in the city, and Yazid - fearful of a revolution that may have begun as a result - freed the captives.
"Zaynab bint Ali quoted as she passed the prostrate body of her brother, Husayn. " O Muhammad! O Muhammad! May the angels of heaven bless you. Here is Husayn in the open, stained with blood and with limbs torn off. O Muhammad! Your daughters are prisoners, your progeny are killed, and the east wind blows dust over them." By God! She made every enemy and friend weep."
Tabari, History of the Prophets and Kings, Volume XIX The Caliphate of Yazid.
Husayn's grave became a pilgrimage site among Shi'a only a few years after his death. A tradition of pilgrimage to the Imam Husayn Shrine and the other Karbala martyrs quickly developed, which is known as Ziarat Ashura. The Umayyad and Abbasid caliphs tried to prevent construction of the shrines and discouraged pilgrimage to the sites. The tomb and its annexes were destroyed by the Abbasid caliph Al-Mutawakkil in 850-851 and Shi'a pilgrimage was prohibited, but shrines in Karbala and Najaf were built by the Buwayhid emir 'Adud al-Daula in 979-80.
It did not take long for public rites of remembrance for Husayn's martyrdom to develop from the early pilgrimages. Under the Buyid dynasty, Mu'izz ad-Dawla officiated at public commemoration of Ashura in Baghdad. These commemorations were also encouraged in Egypt by the Fatimid caliph al-'Aziz. From Seljuq times, Ashura rituals began to attract many participants from a variety of backgrounds, including Sunnis. With the recognition of Twelvers as the official religion by the Safavids, Mourning of Muharram extended throughout the first ten days of Muharram.