French Sign Language family

French Sign Language
Geographic distribution:	Before 1850, Western Europe, and North America; today parts of Europe, the Americas, Africa, and Asia.
Linguistic classification:	One of the world's sign language families
Proto-language:	Old French Sign Language
Glottolog:	lsfi1234

The French Sign Language (LSF) family is a language family of sign languages which includes French Sign Language and American Sign Language.

The FSL family descends from Old French Sign Language, which developed among the deaf community in Paris. The earliest mention of Old French Sign Language is by the abbé Charles-Michel de l'Épée in the late 17th century, but it could have existed for centuries prior. Several European sign languages, such as Russian Sign Language, derive from it, as does American Sign Language, established when French educator Laurent Clerc taught his language at the American School for the Deaf. Others, such as Spanish Sign Language, are thought to be related to French Sign Language even if they are not directly descendant from it.

Henri Wittmann (1991) lists the following suspected members of the family, with date of establishment or earliest attestation:

French Sign Language (1752; may be different from Old French Sign Language)

and, perhaps,

Wittnann believes Lyons Sign Language, Spanish Sign Language, Brazilian Sign Language, and Venezuelan Sign Language, which are sometimes counted in the French family, had separate origins, though with some contact through stimulus diffusion, and it was Lyons rather than French Sign Language that gave rise to Belgian Sign Language. Chilean Sign Language (1852) has also been included in the French family but is not listed by Wittmann.

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