Battle of Akroinon

One division, 20,000 strong under Abdallah al-Battal and al-Malik ibn Shu'aib, was confronted at Akroinon by the Byzantines under the command of Emperor Leo III the Isaurian (r. 717–741) and his son, the future Constantine V (r. 741–775).

Coupled with the Umayyad Caliphate's troubles on other fronts and the internal instability before and after the Abbasid Revolt, this put an end to major Arab incursions into Anatolia for three decades.

Following the disastrous Battle of Sebastopolis, the Byzantines had largely confined themselves to a strategy of passive defence, while the Muslim armies regularly launched raids into Byzantine-held Anatolia.

The raids of this period were also largely confined to the central Anatolian plateau (chiefly its eastern half, Cappadocia), and only rarely reached the peripheral coastlands.

In 742 and 743, the Umayyads were able to exploit a civil war between Constantine V and the general Artabasdos and raid into Anatolia with relative impunity, but the Arab sources do not report any major achievements.

Brooks to more recent ones such as Walter Kaegi and Ralph-Johannes Lilie, have challenged this view, attributing the reduced Arab threat after Akroinon to the fact that it coincided with other heavy reversals on the most remote provinces of the Caliphate (e.g. the battles of Marj Ardabil or The Defile), which exhausted its overextended military resources, as well as with internal turmoil due to civil wars and the Abbasid Revolution.

Indeed, Constantine V was able to take advantage of the Umayyad Caliphate's collapse to launch a series of expeditions into Syria and secure a Byzantine ascendancy on the eastern frontier which lasted until the 770s.