Laborec was an alleged White Croat ruler in the 9th century, who was a vassal of Great Moravia. He is mentioned in Gesta Hungarorum by Bele Regis Notarius. At the time of the Hungarian conquest of the Carpathian Basin around 896, Laborec opposed the conquest of Carpathian Ruthenia by Hungarian tribes led by Árpád, according to the Gesta Hungarorum.
During the 9th century a fortified castle changed into a fortified early feudal town-settlement (now Uzhhorod), which became the centre of a new Slavonic principality, at the head of which was Laborec, who was a vassal of Great Moravia.
When Tsar Simeon the Great began expanding his Bulgarian Empire, he gained control of a segment of "White Croatia", forcing Laborec to recognize his authority at the end of the 9th century. In 896 the Hungarian tribes crossed the Carpathian Range and migrated into Pannonian Basin. Prince Laborec fell from power under the efforts of the Hungarians and the Kievan forces; many of these forces remained behind and were assimilated by the White Croats.
Laborec was defeated and killed on the banks of the Laborec river that still carries his name.
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