Karelian is a variety closely related to Finnish. It belongs to the Finno-Ugric languages, and is chiefly distinguished from standard Finnish by the lack of influence from modern 19th and 20th century Finnish. The Karelian language does not have a standard written form.
The Karelian language is by Finns usually considered a dialect of Finnish, as it is perceived to differ only slightly from standard-Finnish. Others, for instance many foreign linguists and some people in Estonia and Russia, consider the Karelian variety a language of its own (although almost extinct), similarly to how the dialects of Ingria by Finns often are considered dialects of Finnish-proper, but in Estonia often are considered languages of their own; and also similarly to Mešnkieli. As it could also be argued Karelian should be considered separate from Finnish because of its geo-political location within the boundaries of another state, a conclusion might be, that Karelian has a similar relation to Finnish, as has Finland-Swedish to Scandinavian Swedish.
Finnish and Karelian were suppressed and out-lawed during Stalin's Great Purges. Attempts to standardize Karelian with a Cyrillic alphabet were unsuccessful, and today the Karelian republic (of the Russian federation) consider Karelian a dialect of Finnish. Finnish, and not Karelian, was the second official language of Karelia from the Winter War 1940 up until the 1980s, when perestroika began. Since the late 1990s there have been moves to pass special language legislation, which would give Karelian an official status. Finnish has also again been proposed as a second official language for the republic, but the proposal has never taken wind.