Modern Chinese Sign Language has developed mostly since the late 1950's.
Similar to all sign languages and languages in general, CSL has several dialects, of which Shanghai is the most prominent. Aspects of the sign language relate to Chinese character signs.
The first deaf school using Chinese Sign Language was created by the American missionary C.R. Mills and his wife in 1887, but even so American Sign Language did not influence CSL.
Schools and workshops or farms for the deaf are channels that serve to spread and disseminate CSL in China. Others who are disconnected from these gathering places tend to use home sign languages that no one else can understand.
The Chinese National Association of the Deaf, R.O.C. was created by deaf in the US and overseas. The main purpose of the domestic deaf in China was to raise quality of living for the deaf which was behind the quality of living standards provided for the blind and other disabled. The members worked together to better welfare of the deaf, to encourage education of deaf and sign language, and to promote the deaf community.