In 560 (other sources indicate between 555 and 561) the Battle of Cúl Dreimhne, or the Battle of the Book, at north-west Ireland. Some sources describes the cause of the battle as being over the copyright of a book that Saint Columba had copied. Other sources suggest the battle was over the killing of Diarmait of Curnán (son of Áed mac Echach King Connaught), who was under Saint Columba's protection, by Diarmait mac Cerbaill High King of Ireland.