Salih and his brother Abd Allah were among the van of the Abbasid forces which overthrew the Umayyads in 750. The brothers besieged and took the Caliphate's capital, Damascus, and then pursued the last Umayyad caliph, Marwan II, to Egypt where he was captured and killed.^[1][2]

Salih was named as the first Abbasid governor of Egypt on 9 August 750. He kept the post for less than a year, being named governor of the Jund Filastin (Palestine) in March 751. In this capacity, he sent Sa'id ibn Abdallah in the first raiding expedition of the Abbasid era against Byzantine Anatolia.^[1] On 8 October, 753 he was appointed again as governor of Egypt, a post he held until 21 February 755.^[1] At the death of the Caliph al-Saffah, Salih's nephew, in 754, Salih's brother Abd Allah launched a revolt in Syria against the new Caliph al-Mansur, claiming to have been named by the dying Saffah as his successor. Salih refused to join his brother's revolt and even led troops into Syria to help suppress it. He clashed with and defeated Abd Allah's governor of Palestine, al-Hakam ibn Da'ban, while Abd Allah was defeated by Abu Muslim and forced to submit to Mansur.^[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.^[1][4] Salih also appropriated most of the Umayyad dynasty's extensive properties in the area for himself. 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). He died in Syria in 769.^[1]

• Ishaq ibn Sulayman al-Hashimi

• Cobb, Paul M. (2001). White banners: contention in ‘Abbāsid Syria, 750–880. Albany, NY: State University of New York Press. ISBN 0-7914-4880-0.
• Grohmann, Adolph & Kennedy, Hugh (1995). "Ṣāliḥ b. ʿAlī". In Bosworth, C. E.; van Donzel, E.; Heinrichs, W. P. & Lecomte, G. (eds.). The Encyclopaedia of Islam, Second Edition. Volume VIII: Ned–Sam. Leiden: E. J. Brill. p. 985. ISBN 978-90-04-09834-3.