Following the failure of the year-long assault by the Umayyad armies on the Byzantine capital Constantinople in 717–718, a short period of peace followed as the Umayyads licked their wounds, suppressed the rebellion of Yazid ibn al-Muhallab and re-assessed their priorities. When warfare on the Arab–Byzantine frontier recommenced in 720, the strategic focus of the Caliphate had shifted away from outright conquest. The Muslim raids across the Taurus Mountains into Byzantine Asia Minor still occurred regularly every spring and summer, sometimes accompanied by naval raids and followed by a winter expedition; they devastated large tracts of Asia Minor, and destroyed several fortresses; but the Arabs did not attempt to hold on to captured strongholds on the west side of the Taurus Mountains. Byz