Thomas Malory

summary

The Grail quest culminates as the pure Sir Galahad—joined by Percival and Bors—proves himself (sits in the Siege Perilous, draws the enchanted sword), achieves the Sangreal, heals King Pelles and is translated; Percival retires to a hermitage and Bors returns to Arthur.
Later Lancelot, celebrated yet compromised by his love for Queen Guinevere, rescues her, causes deadly schisms (including the accidental deaths of Gareth and Gaheris), and after Modred’s usurpation and Guinevere’s retreat to a nunnery he withdraws from the world.
Civil war follows: Arthur defeats Modred but is mortally wounded, orders Excalibur cast into the lake, is borne away to Avilion, and the Round Table and his realm pass.