Sir Gareth is a Knight of the Round Table in Arthurian legend. He was the youngest son of King Lot and Queen Morgause, King Arthur's half-sister, thus making him Arthur's nephew, as well as brother to Gawain, Agravain, and Gaheris, and either a brother or half-brother of Mordred. He is particularly notable in Le Morte d'Arthur where he is also known by his nickname Beaumains.
