He is said to have been a British king, who, after the death of his queen, resigned the crown to his son, and became a monk in the monastery of Saint David. It is added that he afterwards went into North Britain, and joined Saint Columba in preaching the gospel amongst the Picts, who then inhabited a great part of what is now called Scotland. He founded a monastery at Govane, near the river, Cluyd, converted all the land of Cantire to the faith of Christ, and died a martyr by the hands of infidels, towards the end of the sixth century. He was buried in his monastery of Govane, and divers churches were erected in Scotland under his invocation. But it seems most probable that the Scottish martyr is not the same person with the British king. Colgan supposes him to have been an Irish monk who had lived in the community of Saint Carthag, at Rathane.
- Father Alban Butler. “Saint Constantine, Martyr”. , 1866. CatholicSaints.Info. 10 March 2013. Web. 1 December 2015. <>