The holy and right-believing King '''Constantine of Strathclyde''' also '''Constantine of Govan''' (Welsh: ''Custennin'', Latin: ''Constantinus'') c.570-c.640, was the only son of King [[w:Riderch I of Alt Clut|Riderch Hael]] of [[w:Kingdom of Strathclyde|Strathclyde]] and his queen Languoreth. He appears in the ''[[w:Óengus_of_Tallaght#F.C3.A9lire_.C3.93engusso|Martryology of Oengus]]'' (ca.830) as well as in the Latin hagiography of [[Kentigern of Glasgow|St. Kentigern]] written by the 12th century monk [[w:Jocelyn of Furness|Jocelyn of Furness]], which regards him as a cleric. His [[feast day]] is on [[March 11]].