Sign Languages in Switzerland

[Michael Everson]

According to the SIL Ethnologue, there are three Sign Languages in
Switzerland: Swiss-French Sign Language (Langage gestuelle), Swiss-German
Sign Language (Natürliche Gebärde), and Swiss-Italian Sign Language.

Does anyone know anything about the origin of these languages? I assume
that they arose in association with the school system and so could be said
to have their origins in particular cities. Is this true? Can the three be
localized to particular parts of Switzerland?

Also, is Swiss-German Sign Language related to German Sign Language in any
particular way? And is Swiss-French Sign Language related to French Sign
Language in any particular way?

Thanks to anyone who can help with the taxonomy here.

Michael Everson  **  Everson Gunn Teoranta  **   http://www.egt.ie
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