Battle of Haram The Battle of Haram or Chramon ( modern Nova Palanka ) was fought between the forces of King Stephen II ( r . 1116 – 1131 ) of Hungary and Emperor John II Komnenos ( r . 1118 – 1143 ) of the Byzantine Empire in the year 1128 , or possibly earlier – in 1125 ( the chronology is uncertain ) , in what is now Serbia , and resulted in a major defeat for the Hungarians . Background . John II was married to the Hungarian princess Piroska , and this involved him in the dynastic struggles of the Kingdom of Hungary . In giving asylum to Álmos , a blinded claimant to the Hungarian throne , John aroused the suspicions of King Stephen II of Hungary . John refused a demand from Stephen that Álmos be surrendered to him . The Hungarians , led by the king , then crossed the Danube frontier and invaded Byzantium ' s Balkan provinces . Most authorities place this event in 1127 , with hostilities lasting until 1129 ; however , an alternative chronology has been suggested with the Hungarian attack and Byzantine retaliation taking place in 1125 with a renewal of hostilities in 1126 . The Hungarians attacked Belgrade , Niš , and Sofia ; John , who was near Philippopolis in Thrace , counterattacked , supported by a naval flotilla operating on the River Danube . Battle . After a challenging campaign , the details of which are obscure , John II managed to defeat the Hungarians and their Serbian allies at the fortress of Haram or Chramon , located in modern Nova Palanka , on the Hungarian bank of the Danube . The Hungarian army , under a commander named Setephel as King Stephen was ill , had entrenched itself , defending the line of the Danube . The Byzantine historian John Cinnamus describes John II employing a ruse to allow his army to cross the river . He sent a mercenary force composed of " Ligurian knights " ( Lombards ) and Turks ( probably horse archers ) to threaten a crossing upstream , while he stayed on the shore opposite Haram with the rest of his army . The ruse worked as his army crossed the river at Haram by boat , the emperor himself on board the imperial trireme . An opposed river crossing is one of the most demanding of military operations . The Byzantine army must have been very disciplined and well supported by archers and bolt - firing artillery on the imperial ships . Once on the Hungarian bank of the Danube the Byzantine cavalry then , " with couched lances , scattered the assembled Hungarian forces . " Many Hungarian troops were killed when a bridge they were crossing collapsed as they were fleeing from the Byzantine attack . The Byzantines took Haram , and other Hungarian fortified settlements in the area , and collected a great deal of plunder . The action has been described as a " bloody battle " and a great defeat for the Hungarians . Aftermath . Following his victory over the Hungarians John II launched a punitive raid against the Serbs . Dangerously for the Byzantines the Serbs had aligned themselves with Hungary . Many Serbian prisoners were taken , and these were transported to Nicomedia in Asia Minor to serve as military colonists . This was done partly to cow the Serbs into submission ( Serbia was , at least nominally , a Byzantine protectorate ) , and partly to strengthen the Byzantine frontier in the east against the Turks . The Serbs were forced to acknowledge Byzantine suzerainty once again . In Hungary , the defeat at Haram undermined Stephen II ' s authority and he faced a serious revolt when two counts named ' Bors ' ( possibly Boris Kalamanos ) , and ' Ivan ' were declared kings . Both were eventually defeated , Ivan being beheaded and Bors fleeing to Byzantium . Following this , the Hungarians renewed hostilities , possibly in order that King Stephen could be seen to reassert his authority , by attacking the Byzantine frontier fortress of Braničevo , which was immediately rebuilt by John . Further Byzantine military successes – Choniates mentions several engagements – resulted in a restoration of peace . Cinnamus describes a Byzantine reverse occurring before peace was established , which suggests that the campaign was not entirely one - sided . Hungarian records , however , agree with Choniates in indicating that King Stephen was again defeated and was consequently forced to negotiate a peace on Byzantine terms . The Byzantines were confirmed in their control of Braničevo , Belgrade , and Zemun and they also recovered the region of Sirmium ( called Frangochorion in Choniates ) , which had been Hungarian since the 1060s . The Hungarian pretender Álmos died in 1129 , removing the major source of friction .