Sir Owain was a young and brave man however he was an inexperienced Knight of Camelot. He took the challenge much to the shock and concern of Arthur who told Morgana he should not have picked up the gauntlet and the court due to his inexperience. Arthur stated that they had never seen him fight, however Owain said that he had the same advantage, although Owain had never before fought in mortal combat and the rules were different. Gwen then appeared with a red cloth token Morgana wanted him to wear "for luck", which he takes promising to "wear it with pride". The token is seen later tied to his chain mail. Despite being trained by Arthur in combat he was killed by Tristan de Bois, who had been raised from the dead as a Wraith through necromancy by Nimueh. Nimueh was intending for the Wraith (Tristan) to kill Uther, meaning that he was invulnerable to mortal weapons even though Owain had been able to stab him during their fight. Because of his invulnerability, Tristan managed to kill Sir Owain, who was the first knight to fall at his hand (Excalibur).
As a Knight of Camelot, Owain was trained in sword fighting, however, the full extent of his fighting skills is unknown, since during the duel with Tristan, he mainly defended himself with a shield and only once hit him, which would be fatal if Tristan was not a ghost. However, he was skilled enough to become a Knight of Camelot, before the duel, and after that he trained with other knights because of which, presumed, his skills improved.
Owain appeared to be a favourite of the Lady Morgana. Morgana begged Arthur to take Owain's place in the duel, and gave Owain her favours to wear. She has not been seen taking as much interest in another Knight, infering that she was good friends with Owain. However, this could of been because she saw his death in her dreams or visions, or because she knew Tristan was better in melee (either by guess or by hearing about Tristan and recognizing the seal and armour).
Owain (died in 595) was one of the four sons of Urien, King of Reghed. He fought with his father against the Angles of Bernicia, in 590, and, after his father's death, became the king of Reghed, but not for a long time, since this kingdom lost his sovereignty to the Northumbria's. The principal source of the real existence of Owain, is the bard of Urien, Taliesin, in his poem Gweith Argoed Llwyfain (The Battle of Argoed Llwyfain).
In the legend
Owain takes a major role in Arthurian legends. He was one of the earliest Knights mentioned in Geoffrey of Monmouth' Historia Regum britanniae. Chrétien de Troyes wrote a book about him, Yvain, the Knight of the Lion around 1170 and Thomas Malory, in Le Morte Darthur, made him the son of Morgan le Fay and King Urien, and subsequently the nephew of Arthur.