Despite brief Arab rule, Central Asia successfully retained much of its Iranian characteristic, remaining an important center of culture and trade for centuries after the adoption of the new religion. Mawarannahr continued to be an important political player in regional affairs, as it had been under various Persian dynasties. In fact, the Abbasid Caliphate, which ruled the Arab world for five centuries beginning in 750, was established thanks in great part to assistance from Central Asian supporters in their struggle against the then-ruling Umayyad Caliphate.