Nanjing dialect
A number of theories have been proposed about the origin of the Wutun villagers, and their peculiar dialect. The Chinese linguist Chen Naixiong infers from the vowel distribution of the Chinese lexical items in Wutun speech that their ancestors may have spoken an old Nanjing dialect. Others think that they may have been a group of Hui people (Chinese-speaking Muslims) from Sichuan who, for reasons unknown, converted to Tibetan Buddhism and moved to eastern Qinghai. In any event, historical documents as old as 1585 attest to the existence of the Wutun community.