What is origin of legends about fairies?

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While the term fairy goes back only to the Middle Ages in Europe, analogues to these beings in varying forms appear in both written and oral literature, from the Sanskrit gandharva (semidivine celestial musicians) to the nymphs of Greek mythology and Homer, the jinni of Arabic mythology, and similar folk characters of the Samoans, of the Arctic peoples, and of other indigenous Americans. The common modern depiction of fairies in children's stories represents a bowdlerization of what was once a serious and even sinister folkloric tradition. The fairies of the past were feared as dangerous and powerful beings who were sometimes friendly to humans but could also be cruel or mischievous.
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Fairy lore is particularly prevalent in Ireland, Cornwall, Wales, and Scotland. Fairies are common in literature from the Middle Ages on and appear in the writings of the Italians Matteo Boiardo and Ludovico Ariosto, the English poet Edmund Spenser, the Frenchman Charles Perrault, and the Dane Hans Christian Andersen, among others.
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