Why is a Jew's harp called a Jew's harp?

There are many theories for the origin of the name Jew's harp. According to the Oxford English Dictionary, this name appears earliest in Walter Raleigh's Discouerie Guiana in 1596, spelled "Iewes Harp ". It has also been suggested that the name derives from the French "Jeu-trompe" meaning "toy-trumpet".