Title: al- Riḍā wa-al-Maʾmūn wa-wilāyat al-ʻahd wa-ṣafaḥāt min al-tārīkh al-ʻAbbāsī
Subjects: Abbasids, History
Places: Islamic Empire
People: ʻAlī al-Riḍā ibn Mūsá (d. 818 or 19), Maʾmūn Caliph (786-833)
Time periods: 750-1258