Terrwyn is a Cymric pagan. Her family were originally from the Silures tribe in Escavalon in Cambria, but Terrwyn herself was born in Brittany after they joined the exodus from King Vortigern's rule. Not that she has much memory of Brittany, as they soon joined Aurelius Ambrosius's invasion of Britain. Her father attended the coronation of King Aurelius, but fell at the Battle of Cymen's Shore as part of
the heroic rearguard who gave their lives so the king and the rest of the army could escape. Although tragic, this event inspired Terrwyn to become a squire.