Shimr was a son of Shurahbil (or Aws) Dhi al-Jawshan ibn Qurt al-A'war ibn Amr, a
companion of the Islamic prophet
Muhammad, who settled in Kufa after the Muslim conquest of Iraq. He was from the Mu'awiya al-Dibab clan of the
Banu Kilab, branch of the
Qaysid tribe of the
Hawazinite Banu Amir. Shimr was an ally of the 4th
Rashidun Caliphate Ali () and fought against
Mu'awiya, the governor of
Syria and future founder of the
Umayyad Caliphate, at the
Battle of Siffin, where he received a head wound. He later defected to the Umayyads. When
Ziyad ibn Abihi arrested the pro-Alid
Hujr ibn Adi on the charge of treason in 671, Shimr was among those who testified against Hujr. In 680,
Husayn ibn Ali, a grandson of Muhammad and son of caliph
Ali, sent his cousin
Muslim ibn Aqil to Kufa in response to calls from the pro-Alids to overthrow the Umayyads. Shimr, along with various other tribal notables, aided the governor
Ubayd Allah ibn Ziyad in quelling the rebellion. Shortly afterwards, Husayn arrived in Iraq and was intercepted in the desert of
Karbala outside of Kufa. After Ibn Ziyad consented to a peace proposal from Husayn, Shimr reportedly opposed the proposal and convinced Ibn Ziyad to subdue Husayn with force. Shimr was subsequently sent to Karbala with orders to either force Husayn into submission or to kill him in case of refusal. A day before the battle, Shimr offered
safe conduct to three paternal brothers of Husayn, including
Abbas ibn Ali, whose mother,
Umm al-Banin, was from the tribe of Shimr. The offer was declined because Husayn was not offered any safe conduct. On the battle day (10 October), Shimr commanded the left wing of the Umayyad army. Upon the orders of the commander of the army,
Umar ibn Sa'd, Shimr set on fire the tents of Husayn's companions, and was intent on burning Husayn's personal tent before being prevented by his own comrades. After a day of conflict, Husayn suffered many casualties, but the Umayyad soldiers hesitated to kill Husayn. Shimr encouraged them to kill him: "Shame on you! Why are you waiting for the man? Kill him, may your mothers be deprived of you!" Shimr then led the final assault. Some accounts name him as the one who ultimately killed and decapitated Husayn, while other accounts name Sinan ibn Anas. He then attempted to kill Husayn's surviving son
Zayn al-Abidin, but was prevented by Ibn Sa'd. Afterwards, Shimr led the escort carrying the heads of the dead to Kufa. Later he accompanied the prisoners to Syria. He is reported to have regretted his actions later in his life. During the rule of
Mukhtar al-Thaqafi, who had seized Kufa in October 685, Shimr was among the agitators who attempted to topple Mukhtar. After the rebellion was defeated, Shimr escaped to Sadama, a place between Kufa and
Basra.
Mus'ab ibn al-Zubayr ruled Basra at the time and Shimr wrote him a letter requesting assistance. The letter was intercepted by Mukhtar's soldiers led by
Abu Amra Kaysan. With his location thus exposed, Shimr was found and killed. Other variants suggest that he was wounded and sent to Mukhtar, who then killed him. ==Descendants==