His real name was Léon Leclère. Described in the Larousse encyclopedia as an "aimable dilettante", he was a writer, composer, and a theorist and practitioner of painting - and a prominent member of the Apaches. He was director of Vogue from 1895 to 1901. Among his works were Humoresques (1921) and various studies on art; but it was his large group of poems called Shéhérazade, published in the early 1900s, which was of special significance for Ravel, when he selected three of them for his song cycle Shéhérazade in 1903.
When Ravel composed his Trois chansons in 1914/15, he dedicated the first song, Nicolette, to Klingsor.
Tristan Klingsor described his long acquaintance with Ravel, particularly during the years of the Apaches, in an essay called L'Époque Ravel, published in 1939 in Maurice Ravel par quelques-uns de ses familiers (Colette, , pp.125-139).