The Principality of Lower Pannonia or Balaton Principality was a Frankish vassal principality, or according to others a Frankish comitatus, led initially by a dux (Pribina) and later by a comes (Pribina's son, Kocel). It was a Slavic polity (Kocel's title was "Comes de Sclauis" - Count of the Slavs) and situated mostly in Transdanubia region. Its capital was Mosapurc "Mosapurc regia civitate", present-day Zalavár (in Old-Slavonic Blatengrad, in Latin Urbs Paludarum).
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