In 1183 , Stefan Nemanja formed a new alliance , with King Bela III of Hungary , and invaded Byzantine soil . Andronicus Comnenus had taken over the imperial throne , but was not recognized . The Massacre of the Latins in Constantinople inflamed the tense political situation . Kulin Ban of Bosnia also joined Nemanja . The Byzantine forces in the eastern Serb borderlands were led by Alexios Branas and Andronikos Lapardas . Inner fights occurred , as Branas supported the new Emperor and Lapardas , opposing , deserted with his troops . The Hungarian-Serbian military soon pushed the Byzantines out of the Morava Valley and advanced all the way to Sofia , raiding Belgrade , Braničevo , Ravno , Niš en route . However , the Hungarians soon withdrew , leaving Nemanja 's forces raiding across western Bulgaria , northern and eastern Macedonia , and the theme of Dyrrachium
Massacre of the Latins
Massacre of the Latins
Stefan Nemanja