From an Old French form of HELEN
. It appears in Arthurian legend; in Thomas Malory's 15th-century compilation 'Le Morte d'Arthur' Elaine was the daughter of Pelleas, the lover of Lancelot
, and the mother of Galahad
. It was not commonly used as an English given name until after the appearance of Tennyson's Arthurian epic 'Idylls of the King' (1859).