When asked by her father to quantify her love, Cordelia answered honestly that she loved him just as any daughter loved a father. Her sisters lied and cajoled Leir. Leir divided Britain between Regan, Goneril, and their husbands, and exiled Cordelia to France, where she married King Aginappus. Eventually, after he had been dispossessed and humiliated, Leir came to realize his mistake.
He traveled to France, reconciled with Cordelia, and amassed an army to retake Britain from his daughters and sons-in-law. The expedition was successful and Leir ruled for three years.
When Leir died, Cordelia succeeded him to the throne. Cordelia buried her father in an underground chamber beneath the River Soar in Leicestershire. This chamber, to which all the local craftsmen used to come at the beginning of each year to perform their first act of labour, was later dedicated to the Roman god Janus. She ruled five years before her nephews, Margan and Cunedag, rebelled against her and imprisoned her. She took her own life in prison.
It has been suggested that she has her origins in Creiddylad (Creiddyledd).
Historia Regum Britanniae | Geoffrey of Monmouth, c. 1138