Harun al-Rashid’s idyllic reign was followed by the struggle among his two sons, Amin and Ma’mun. Soon expanding to their military support among the Arab and Perso-Turkic factions (respectively) in the court, this struggle threatened to end the Abbasid power altogether. Abdullah al-Mam’mun finally came out as the winner in 813 and ruled until 833, continuing and expanding the cultural renaissance of the period of his father. It was under al-Ma’mun’s rule that the first centers of translation= and learning were established in Baghdad, where great works of Indian, Persian, Greek, and Syriac learning were translated into Arabic, allowing for the flourishing of Muslim learning itself. Baghdad was by this time truly transformed into a cosmopolitan city, where adherents of all faiths gathered, disputed about the merits of their belief, and contributed to a common pool of learning and progress. The economy also continued to develop, now directing the route of most trade from south, central and east Asia through Baghdad and Basra, the largest cities in Mesopotamia (Source: Iranologie).