Salih and his brother Abd Allah were among the van of the Abbasid forces which overthrew the Umayyads in 750.
In this capacity, he sent Sa'id ibn Abdallah in the first raiding expedition of the Abbasid era against Byzantine Anatolia.
Salih refused to join his brother's revolt and even led troops into Syria to help suppress it.
[3] Despite Abd Allah's rebellion, Salih and his family were established as the paramount Abbasid potentates in Syria, a position they held for the next half-century, as Salih's sons al-Fadl, Ibrahim and Abd al-Malik all held governorships in Syria and Egypt.
In addition, he played an important role in the strengthening of the Abbasid-Byzantine frontier, the thughur, re-occupying and rebuilding the former Byzantine cities of Melitene (Malatya), Germanikeia (Mar'ash) and Mopsuestia (al-Massisa).