Arthur Rex: A Legendary Novel is a 1978 novel by American author Thomas Berger. Berger offers his own take on the legends of King Arthur, from the heroic monarch's inauspicious conception, to his childhood in bucolic Wales, his rise to the throne, his discovery of the great sword Excalibur, his establishment of the Knights of the Round Table, his long and honorable reign, and his heroic death in battle against the evil Mordred, his bastard son.