Gildas mentions Constantine in chapters 28 and 29 of his 6th-century work "De Excidio et Conquestu Britanniae". He is one of five Brittonic kings whom the author rebukes and compares to Biblical beasts. Gildas calls Constantine the "tyrannical whelp of the unclean lioness of Damnonia", a reference to the books of Daniel and Revelation, and apparently also a slur directed at his mother. This "Damnonia" is generally identified as the kingdom of Dumnonia in Southwestern Britain. Scholars such as Lloyd Laing and Leslie Alcock note the possibility that Gildas may have instead intended the territory of the Damnonii, a tribe in present-day Scotland mentioned by Ptolemy in the 2nd century, but others such as Thomas D. O'Sullivan consider this unlikely.