Tartarian Empire refers to a group of pseudohistorical conspiracy theories, including ideas of a "hidden past" and "mud floods" which originated as pseudoscientific Russian nationalism. Tartary or Tartaria is a historical name for Central Asia and Siberia. Conspiracy theories assert that Tartary or the Tartarian Empire was a lost civilization with advanced technology and culture. This ignores the well-documented history of Asia, which Tartary refers to. In the present day, the Tartary region covers a region spanning from central Afghanistan to northern Kazakhstan, as well as areas in present Mongolia, China and the Russian Far East in "Chinese Tartary".

The new chronology is a pseudohistorical theory proposed by Anatoly Fomenko who argues that events of antiquity generally attributed to the ancient civilizations of Rome, Greece and Egypt actually occurred during the Middle Ages, more than a thousand years later.