Lower, Mark A (1860) Patronymica Britannica: a dictionary of the family names of the United Kingdom. London: J.R. Smith. Public Domain.
CLIFFORD
As described in historical dictionaries
Patronymica Britannica (1860)
CLIFFORD. The noble family, suruamed from Clifford (tlieir castle and lauds in CO. Hereford, which they acquired in marriage in the XII. cent.), came from Normaudy with the Conqueror, and then bore the name of Fitz Pons. They claimed lineal descent from Ricliard, Duke of Normandy, the grandfather of \\'iliam I. In charters, the name is latinized De Clivo Forte.
Surname type: Location or geographical feature
Origin: English
Region of origin: British Isles
Country of origin: England
Religion of origin: Christian
Language of origin: English