Sir Lancelot slayed a dragon and King Pelles invited him back to his castle. King Pelles wanted Sir Lancelot to marry his daughter Elaine, and tricked him into believing Elaine was Guenevere with a magic potion. Lancelot awoke to find Elaine in his bed, and not Guinevere. He knew he had been tricked, apologised to Elaine and bade her farewell. Elaine later gave birth to a son she called Galahad.
Elaine heard that Lancelot was at Camelot, went there, but he would not speak to her. Lancelot was again tricked into visiting Elaine by believing that he was going to Queen Guenevere's room. The Queen found out about Elaine and Lancelot, and sent Lancelot away from the court. After two years of aimless wandering Lancelot was ragged and had mad. He arrived at the city of Corbin where Elaine lived with their son Galahad. King Pelles had him taken to the Holy Grail and he was cured of his madenss by its powers. Sir Lancelot and Elaine moved to his castle called "Joyous Gard". After some months Sir Percivale and Sir Ector arrived to ask Sir Lancelot to return to the round table and to King Arthur.
Sir Lancelot was also the object of the affections of Elaine the Lily Maid of Astolat who died of a broken heart when he rejected her. An old story tells how, while visiting her father, Lancelot went riding in Windsor Forest. He fell asleep by St. Leonard’s Well , just as a lady and her hunting party arrived chasing a deer. It was Sir Thomas Malory who named her Elaine, living at Astolat. Tennyson follows Malory and in the "Idylls of the King", refers to her as "the lily maid of Astolat" but also adopts her name to create "The Lady of Shalott". Elaine of Astolat dies as a result of unrequited love, and a boat bearing her body comes to Camelot. Many medieval writers told different versions of the same story.
In Mort Artu, she tries to trick Sir Lancelot into wearing her sleeve in the tournament, and boldly declares her love.
In Morte Arthur it claims that Lancelot sees that the maid has fallen in love
with him and follows her to her
chamber to comfort her, where he agrees to wear the sleeve to the tournament
as the alternative to becoming involved with her.
Malory claims that Lancelot is blind to Elaine's passion and only agrees to wear the sleeve only because he thinks it will fool his brothers and cousins in the tournament. Malory's Elaine is a real woman and her farewell letter asks Lancelot to pray for her.
Lancelot & Elaine, by Alfred Lord Tennyson