Conchobar: son of Cathba the druid, and of Ness, and foster-son of Fachtna Fatach (variously pronounced Cruhóor, Connahóor)
Conlaech: son of Cuchulain and Aifè
Corcumruad: the present barony of Corcomroe, in the County Clare
Cormac Conlongas: King Conchobar's eldest son; called "the Intelligent Exile," because of the part he took as surety for the safety of the exiled sons of Usnech
Coronn: the barony of Corran, in the County Sligo
Corp Cliath: a place in Ulster
Craeb ruad: ordinarily Englished "Red Branch"; better, perhaps, "Nobles' Branch:" King Conchobar's banqueting-hall, at Emain Macha
Crannach: at Faughart, north-east of Fid Mor
Cromma: a river flowing into the Boyne not far from Slane