Jovan Vladimir or John Vladimir (Serbian Cyrillic: Јован Владимир; ca. 990 – 22 May 1016) was the ruler of Duklja, the most powerful Serbian principality of the time, from around 1000 to 1016. He ruled during the protracted war between the Byzantine Empire and the First Bulgarian Empire. Vladimir was acknowledged as a pious, just, and peaceful ruler. He is recognized as a martyr and saint, with his feast day being celebrated on 22 May.
Jovan Vladimir had a close relationship with Byzantium but this did not save Duklja from the expansionist Tsar Samuel of Bulgaria, who conquered the principality in around 1010 and took Vladimir prisoner. A medieval chronicle asserts that Samuel's daughter, Theodora Kosara, fell in love with Vladimir and begged her father for his hand. The tsar allowed the marriage and returned Duklja to Vladimir, who ruled as his vassal. Vladimir took no part in his father-in-law's war efforts. The warfare culminated with Tsar Samuel's defeat by the Byzantines in 1014 and death soon after. In 1016 Vladimir fell victim to a plot by Ivan Vladislav, the last ruler of the First Bulgarian Empire. He was beheaded in front of a church in Prespa, the empire's capital, and was buried there. He was soon recognized as a martyr and saint. His widow, Kosara, reburied him in the Prečista Krajinska Church, near his court in southeastern Duklja. In 1381 his remains were preserved in the Church of St Jovan Vladimir near Elbasan, and since 1995 they have been kept in the Orthodox cathedral of Tirana, Albania. The saint's remains are considered Christian relics, and attract many believers, especially on his feast day, when the relics are taken to the church near Elbasan for a celebration.
The cross Vladimir held when he was beheaded is also regarded as a relic. Traditionally under the care of the Andrović family from the village of Velji Mikulići in southeastern Montenegro, the cross is only shown to believers on the Feast of Pentecost, when it is carried in a procession to the summit of Mount Rumija. Jovan Vladimir is regarded as the first Serbian saint and the patron saint of the town of Bar in Montenegro. His earliest, lost hagiography was probably written sometime between 1075 and 1089; a shortened version, written in Latin, is preserved in the Chronicle of the Priest of Duklja. His hagiographies in Greek and Church Slavonic were first published, respectively, in 1690 and 1802. The saint is classically depicted in icons as a monarch wearing a crown and regal clothes, with a cross in his right hand and his own head in his left hand. He is fabled to have carried his severed head to his place of burial.