One of the most important of the less-remembered knights, Baudwin seems to have been a major figure in various pre-Malory romances. In The Avowynge of King Arthur we learn that he made three interesting vows prompted by early experiences campaigning in Spain; never to deny anyone meat and drink, never to fear death, and never to be jealous of his wife or any other woman. It is possible that Sir Baudwin should be identified with Bishop Baudwin (Baldwin).
The little Malory gives about him is telling. On Arthur’s accession, he made Sir Baudwin constable of the kingdom at the same time he made Kay seneschal. When Arthur left for his war against the Emperor of Rome, he made Baudwin joint governor of England in his absence, along with the Sir Constantine who later succeeded to the throne of Britain.
Later, apparently after the death of his wife, Baudwin became a holy hermit and a
full noble surgeon and a good leech [physician],
forsaking his lands to settle in “wilful poverty” with at least two servants somewhere in the neighborhood of Camelot and Astolat. His hermitage was
under a wood, and a great cliff on the other side, and a fair water running under it
some two or three miles from Camelot. Here, after the tournament at Winchester, Baudwin healed the gravely wounded Lancelot, whom he recognized by a scar on the latter’s neck.
Malory first mentions Baudwin as one of the protectors of the boy king Arthur. When Arthur first establishes the lands about London following his crowning at the Pentecost feast, he makes Baudwin constable, probably the equivalent of the local military commander.
Elaine of Astolat | The Legend of King Arthur