Druidic bards, or filid (filidh, fili), passed on the myths of the Celts from generation to generation in Ireland until well into the age of Christian dominance beginning in the sixth century C.E. The monks who wrote down the old tales at least had a reasonably accurate source from which to work, as the oral tradition was strong and practiced with great care. Many of these early writings, however, were destroyed and only recovered in part; they are included in the compilations of the eleventh and twelfth centuries such as The Book of the Dun Cow, The Book of Leinster, and most important, The Book of Invasions. Naturally the monks who did the compilations interjected something of their own faith into the old myths. In one version of the creation of Ireland, for instance, it was said that it was Cesair, the granddaughter of Noah, who, with her father, “discovered” Ireland after seven years in an ark during the great flood. Still, there was a sufficient nationalistic and ethnic interest in Ireland to assure at least a reasonable transmission of the old myths, especially since Ireland was not greatly affected by the Roman invasion of Great Britain.