DE BURGH. The Marquis Clanricarde deduces his descent from Charles, 5th son of the Emperor Charlemagne, who was the common ancestor of the counts of Blois, the kings of Jerusalem, the great baronial De Burghs of England, the Burkes of Ireland, and a number of otlier ancient families. The surname is said to have been assumed by John, earl of Comj-n, in the XI. cent.

Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.