Until 1956, when American Andrew Foster introduced American Sign Language (ASL) to Africa, the only deaf schools in Africa were in Egypt and South Africa. Foster worked for three decades, until his death in 1986, to promulgate the use of sign language across the continent. Local variations emerged, including Ghanaian Sign Language and Nigerian Sign Language, both dialects of ASL. This still-developing field is sure to throw up many more fascinating dialectal differences, as the education of the deaf continues to improve in Africa.
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