Geoffrey of Monmouth's "Historia Regum Britanniae" ("History of the Kings of Britain"), written in the 1130s, introduced the legend of King Arthur, which was to be important to the development of chivalric ideals in literature. Sir Thomas Malory's "Le Morte d'Arthur" ("The Death of Arthur"), written in 1469, was important in defining the ideal of chivalry, which is essential to the modern concept of the knight, as an elite warrior sworn to uphold the values of faith, loyalty, courage, and honour.