Sir Gawain is one of the notable knights of the Round Table. He is the loyal and loving nephew of Arthur, the child of the King's sister Morgause and her husband King Lot of Lothian (to which popular, if erroneous, etymology makes him the eponym). Gawain is brother to Sir Agravain, Sir Gaheris, Sir Gareth and Sir Mordred. Various texts use other names for the hero: Gwalchmai, the name of an older sun-god, in the earliest Welsh tales and various transliterations such as Gauvain, Walewein and Walgan.
Although Gawain is often lauded as a good knight, heis not permitted to 'achieve' the Grail. This, apparently, is connected with his reputation as 'the Maidens' knight' - his courtesy towards women and the tradition of courtly love.