is debated. Japanese has been grouped with language families such as Ainu, Austroasiatic, and the now-discredited Altaic, but none of these proposals has gained widespread acceptance. Little is known of the language's prehistory, or when it first appeared in Japan. Chinese documents from the 3rd century recorded a few Japanese words, but substantial texts did not appear until the 8th century. During the Heian period (794–1185), Chinese had considerable influence on the vocabulary and phonology of Old Japanese. Late Middle Japanese (1185–1600) included changes in features that brought it closer to the modern language, and the first appearance of European loanwords.