Battle of Beroia The Battle of Beroia ( modern Stara Zagora ) was fought between the Pechenegs and Emperor John II Komnenos ( r . 1118 – 1143 ) of the Byzantine Empire in the year 1122 in what is now Bulgaria , and resulted in the disappearance of the Pecheneg people as an independent force . Background . In 1091 , the Pechenegs had invaded the Byzantine Empire , and had been crushingly defeated by John II ' s father Alexios I Komnenos ( r . 1081 – 1118 ) at the Battle of Levounion . This defeat had meant the almost total extinction of all the Pechenegs who had taken part in the expedition ; however , some Pecheneg groups had not been involved in the invasion . Attacked again in 1094 by the Cumans , many of the remaining Pechenegs were slain or absorbed . Yet even so , some bands continued in their independence . In 1122 , Pechenegs from the Russian steppes invaded the Byzantine Empire by crossing the Danube frontier into Byzantine territory . According to Michael Angold , it is possible that their invasion took place with the connivance of Vladimir Monomakh ( r . 1113 – 1125 ) , the ruler of Kiev , given that the Pechenegs had once been his auxiliaries . It is recorded that the remnants of the Oghuz and the Pechenegs had been expelled from Russia in 1121 . The invasion posed a serious threat to Byzantine control over the northern Balkans . Emperor John II Komnenos of Byzantium , determined to meet the invaders in the field and drive them back , transferred his field army from Asia Minor ( where it had been engaged against the Seljuk Turks ) to Europe , and prepared to march north . Battle . The Byzantine emperor gathered his forces near Constantinople , and set out to meet the Pecheneg army as soon as possible . Meanwhile , the Pechenegs had crossed the Haemus Mountains ( Balkan Mountains ) and encamped themselves near the city of Beroia in Thrace . The emperor at first offered the Pecheneg chiefs presents , offering to grant them a treaty that was favourable to their interests . The Pechenegs were successfully duped by this deception , and were as a result taken by surprise when the Byzantines suddenly launched a major attack on their defensive wagon laager . The Pechenegs fought as waves of horse archer s , firing arrows continuously . They relied on their wagon laager as a rallying point , depot for arrow resupply and a point of last defence . The battle was hard fought and John was wounded in the leg by an arrow . However , the Byzantines forced the Pechenegs back and penned them in their laager . This defence proved effective , and it was not until John led the Varangian Guard , the elite heavy infantry force of the Byzantine emperors , against the wagons that their protection was breached . The Varangians , armed with their distinctive Danish axe s , hacked their way through the Pecheneg circle of wagons , collapsing the Pecheneg position and causing a general rout in their camp . The Byzantine victory was complete , and the Pecheneg survivors were taken captive and enlisted into the Byzantine army . Aftermath . The Byzantine victory effectively destroyed the Pechenegs as an independent force . For some time , significant communities of Pechenegs remained in Hungary , but eventually the Pechenegs ceased to be a distinct people and were assimilated by neighbouring peoples such as the Bulgarians and Magyars . For the Byzantines , the victory did not immediately lead to peace since the Hungarians attacked Branitshevo , the Byzantine outpost on the Danube , in 1128 . Yet , the victory over the Pechenegs , and later the Hungarians , ensured that much of the Balkan peninsula would remain Byzantine , which in turn allowed John to concentrate on extending Byzantine power and influence in Asia Minor and the Holy Land .