fourth Umayyad ruler of Muslim Spain who enjoyed a reign (822–852) of brilliance and prosperity, the importance of which has been underestimated by some historians.

ʿAbd ar-Raḥmān II was the grandson of his namesake, founder of the Umayyad dynasty in Spain. His reign was an administrative watershed. As the influence of the ʿAbbā sid Caliphate, then at the peak of its splendour, grew, Córdoba's (Córdoba, Mosque-Cathedral of) administrative system increasingly came into accord with that of Baghdad, the ʿAbbāsid capital. ʿAbd ar-Raḥmān carried out a vigorous policy of public works, made additions to the Great Mosque in Córdoba, and patronized poets, musicians, and men of religion. Although palace intrigues surrounded his death in 852, they did not diminish his accomplishments.