Historical linguists who specialize in Japanese agree that it is one of the two members of the Japonic language family, the other member being Ryūkyūan. (An older view, still held by many non-specialists, is that Japanese is a language isolate, of which the Ryūkyūan languages are dialects.)
The genetic affiliation of the Japonic family is uncertain. Numerous theories have been proposed, relating it to a wide variety of other languages and families, including extinct languages spoken by historic cultures of the Korean Peninsula; the Korean language; the Altaic languages; and the Austronesian languages, among many others. It is also often suggested that it may be a creole language combining more than one of these. The various theories are detailed in the main article. At this point, no one theory is generally accepted as correct, and the issue is likely to remain controversial.
