Solresol is a constructed language devised by François Sudre, beginning in 1827. His major book on it, Langue musicale universelle, was published after his death in 1866, though he had already been publicizing it for some years. Solresol enjoyed a brief spell of popularity, reaching its pinnacle with Boleslas Gajewski's 1902 posthumous publication of Grammaire du Solresol.
The teaching of sign languages to the deaf was discouraged between 1880 and 1991 in France, contributing to Solresol's descent into obscurity. After a few years of popularity, Solresol nearly vanished in the face of more successful languages, such as Volapük and Esperanto. There is still a small community of Solresol enthusiasts scattered across the world, better able to communicate with one another now more than before thanks to the Internet.