 Al-Muhallab's descendants, known as the Muhallabids, became a highly influential family, many of whose members held high office under various Umayyad and Abbasid caliphs, or became well-known scholars.Throughout his early military career, he participated in the Arab campaigns against the Persians in Fars, Ahwaz, Sistan and Khurasan during the successive reigns of caliphs Umar (), Uthman (), Ali () and Mu'awiya I ().By 680, his tribe, the Azd of Oman, had become a major army faction in the Arabs' Basra garrison, the launchpad for the Persian conquest.