Battle of Keramaia

Leo III the Isaurian's son and successor, Constantine V, won noteworthy victories in northern Syria and also thoroughly undermined Bulgarian strength. In 746, profiting from the unstable conditions in the Umayyad Caliphate, which was falling apart under Marwan II, Constantine V invaded Syria and captured Germanikeia, and the Battle of Keramaia resulted in a major Byzantine naval victory over the Umayyad fleet. Coupled with military defeats on other fronts of the Caliphate and internal instability, Umayyad expansion came to an end.