The inscription on these coins is well worthy of notice...

The inscription on these coins is well worthy of notice: “The King of God and the faith, Al-Ma’mun, Amir and Khalifa of the faithful, and al-Riḍa, the Imam of the Muslims.” He then announced to those he had summoned, that he had carefully considered all the descendants of Abbas and also the descendants of ‘Ali, and that he had not found in his search anyone more worthy or fitter to be his successor than ‘Ali al-Riḍa.

He, therefore, took him by the hand and publicly acknowledged him as his successor (Kulayni). Once this story of succession was announced Ma’mun’s political ambition was achieved, as he has secured the help of the Persians fully behind him and he considered himself the sole ruler of the Abbasid Empire.

However, Ma’mun was still not secure on his throne, as the Arab party who sided with Amin, never liked the appointment of Imam ‘Ali al- Riḍa (PBUH) as the successor of Ma’mun, no matter how dubious it looked to them on the face of it. While Imam Riḍa was with Mamun in Merv, his Prime…