al-Ḥasan b. Sahl (d. 236/850), an ʿAbbāsid official and vizier under caliph al-Maʾmūn (r. 198-218/833-32), and brother of al-Faḍl b. Sahl 'Dhū al-Riyāsatayn' ('the man of the two chieftainships') (d. 202/818).

There is little information about al-Ḥasan's life before he became an ʿAbbāsid official. Some biographers trace his family's lineage to the ancient kings of Iran (Ibn al-Ṭiqṭaqā, 221). Sahl, the father of al-Ḥasan and al-Faḍl, was the son of Zādhānfarrukh, and came from the village of Ṣābir Nīthā in Sīb Aʿlā, a dependency of Kūfa (al-Jahshiyārī, 182; Yāqūt, 3/359). The nisba 'al…