 The other center of power in the area, Sultanate of Buayan, which is now modern General Santos City, has an even longer history dating back to early Arab missionaries, who, although not able to implant the Islamic faith, introduced a more sophisticated political system.In Buayan, the transition to Islam took a longer time.Spanish chronicles was told that Buayan, and not Cotabato, was the most important settlement in Mindanao at that time.