Suibne's death is recorded in 1034 by the fifteenth- to sixteenth-century "Annals of Ulster", the fourteenth-century "Annals of Tigernach", and the sixteenth-century "Annals of Loch Cé". These three sources accord him the title ""ri Gall-Gaidhel"", ""rí Gall-Gáedel"", and ""rí Gall Goeidil"". This style which could be evidence that Suibne ruled in either the Isles, Galloway, or somewhere along the south-western coast of Scotland north of the Solway Firth. In fact, little is certain of Suibne, as he is not attested by any other historical source.