Battle of Akroinon The Battle of Akroinon was fought at Akroinon or Akroinos ( near modern Afyon ) in Phrygia , on the western edge of the Anatolian plateau , in 740 between an Umayyad Arab army and the Byzantine forces . The Arabs had been conducting regular raids into Anatolia for the past century , and the 740 expedition was the largest in recent decades , consisting of three separate divisions . 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 ) . The battle resulted in a decisive Byzantine victory . 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 . Background . Since the beginning of the Muslim conquests , the Byzantine Empire , as the largest , richest and militarily strongest state bordering the expanding Caliphate , had been the Muslims ' primary enemy . Following the disastrous Battle of Sebastopolis , the Byzantines had largely confined themselves to a defensive strategy , while the Muslim armies regularly launched raids into Byzantine - held Anatolia . Following their failure to capture the Byzantine capital , Constantinople , in 717 – 718 , the Umayyads for a time diverted their attention elsewhere . From 720 / 721 , however , they resumed these expeditions in a regular pattern : each summer one or two campaigns ( pl . " ṣawā ' if " , sing . " ṣā ' ifa " ) would be launched , sometimes accompanied by a naval attack and / or followed by winter expeditions ( " shawātī " ) . These were no longer aimed at permanent conquest but rather large - scale raids , plundering and devastating the countryside and only occasionally attacking forts or major settlements . 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 . Under the more aggressive Caliph Hisham ibn Abd al - Malik ( r . 723 – 743 ) , these raids became more important and were led by some of the Caliphate ' s most capable generals , including princes of the Umayyad dynasty , like Maslama ibn Abd al - Malik or Hisham ' s own sons Mu ' awiyah , Maslama and Sulayman . Gradually , however , the Muslim successes became fewer , especially as their resources were drawn into the mounting conflict with the Khazars . The raids continued , but the Arab and Byzantine chroniclers mention fewer successful captures of forts or towns . Nevertheless , after a major victory over the Khazars in 737 relieved them of pressure in the Caucasus , the Arabs intensified their campaigns against Byzantium : in 738 and 739 , Maslamah ibn Hisham achieved a number of successes including the capture of the town of Ancyra . For the year 740 , Hisham assembled the largest expedition of his reign , placing it under his son Sulayman . Battle . According to the " Chronicle " of Theophanes the Confessor , the Umayyad force totalled 90 , 000 men . 10 , 000 lightly armed men under al - Ghamr ibn Yazid were sent to raid the western coast , followed by 20 , 000 under Abdallah al - Battal and al - Malik ibn Su ' aib who marched towards Akroinon , while the main force of some 60 , 000 ( this last number is certainly much inflated ) , under Sulayman ibn Hisham , raided Cappadocia . The Emperor Leo confronted the second force at Akroinon . Details of the battle are not known , but the Emperor secured a crushing victory : both Arab commanders fell , as well as the larger part of their army . About 6 , 800 , however , resisted and managed to conduct an orderly retreat to Synnada , where they joined Sulayman . The other two forces devastated the countryside unopposed , but failed to take any towns or forts . In addition , the Arab invasion army suffered from severe hunger and lack of supplies before returning to Syria . The 10th - century Arab Christian historian Agapius also records that the Byzantines took 20 , 000 prisoners from the invading forces . Effect and aftermath . Akroinon was a major success for the Byzantines , as it was the first large - scale victory they had scored in a pitched battle against the Arabs . Seeing it as evidence of God ' s renewed favour , the victory also served to strengthen Leo ' s belief in the policy of iconoclasm that he had adopted some years before . In the immediate aftermath , this success opened up the way for a more aggressive stance by the Byzantines , who in 741 attacked the major Arab base of Melitene . In 742 and 743 , the Umayyads were able to exploit a civil war between Constantine V and Artabasdos and raid into Anatolia with relative impunity , but the Arab sources do not report any major achievements . The Arab defeat at Akroinon has traditionally been seen as a " decisive " battle and a " turning point " in the Arab – Byzantine Wars , causing the slackening of Arab pressure on Byzantium . Other historians however , from the early 20th - century Syriac scholar E . W . 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 , which exhausted its overextended military resources , as well as with internal turmoil due to civil wars and the Abbasid Revolution . As a result , the Arab attacks against the Byzantine Empire in the 740s were rather ineffectual and soon ceased completely . 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 . In the Muslim world , the memory of the defeated Arab commander , Abdallah al - Battal , was preserved , and he became one of the greatest heroes of Arab and later Turkish epic poetry as " Sayyid Battal Ghazi " .