Tags: Christian Bishop.
John (died 1147) was an early 12th-century Tironensian cleric. He was the chaplain and close confident of King David I of Scotland before becoming Bishop of Glasgow and founder of Glasgow Cathedral. He was one of the most significant religious reformers in the history of Scotland. His later nickname Achaius a latinisation of Eochaid would indicate that he was Gaelic but the name is probably not authentic.