Al-Harith was a son of the prominent pre-Islamic Qurayshite Hisham ibn al-Mughira of the Banu Makhzum clan in Mecca.
[2] Al-Harith's brother was Abu Jahl, the leader of Meccan opposition to the Islamic prophet Muhammad until his death at the Battle of Badr in 624.
[3] Afterward, he fought in the Muslim army against the Arab polytheists at the Battle of Hunayn in 630 and was given a share of the war spoils from that engagement.
[4] Al-Harith participated in the Muslim conquest of Syria,[3] successively fighting in the battles of Ajnadayn in Palestine and Fahl in Transjordan, both in 634.
The Shihab dynasty, the former ruling house in Ottoman-era Mount Lebanon are purported descendants of al-Harith ibn Hisham.