Abu Mansur Muhammad ibn Ahmad al-Mu'tadid, usually known simply by his regnal title al-Qahir bi'llah, was the nineteenth caliph of the Abbasid Caliphate from 932 to 934. He was born 286 AH and died 339 AH.

Abū al-ʿAbbās Aḥmad ibn Ṭalḥa al-Muwaffaq, 853/4 or 860/1 – 5 April 902, better known by his regnal name al-Muʿtaḍid bi-llāh, was the caliph of the Abbasid Caliphate from 892 until his death in 902.