Jovan Vladimir was a Serbian prince who ruled the principality of Duklja from approximately 1000 until his death in 1016. Governing during a period of intense conflict between the Byzantine and Bulgarian Empires, he was known as a peaceful and just leader. After being captured by Tsar Samuel of Bulgaria, he was eventually released to rule as a vassal following his marriage to the tsar's daughter, Theodora Kosara. His life ended when he was executed by a political plot in Prespa, leading to his recognition as a martyr.