Tartary (Latin: Tartaria; French: Tartarie; German: Tartarei; Russian: Тартария, romanized: Tartariya) or Tatary (Russian: Татария, romanized: Tatariya) was a blanket term used in Western European literature and cartography for a vast part of Asia bounded by the Caspian Sea, the Ural Mountains, the Pacific Ocean, and the northern borders of China, India and Persia, at a time when this region was largely unknown to European geographers.

The active use of the toponym (place name) can be traced from the 13th to the 19th centuries. In European sources, Tartary became the most common name for Central Asia that had no connection with the real polities or ethnic groups of the region; until the 19th century, European knowledge of the area remained extremely scarce and fragmentary. In modern English-speaking tradition, the region formerly known as Tartary is usually called Inner or Central Eurasia. Much of this area consists of arid plains, the main nomadic population of which in the past was engaged in animal husbandry.

Ignorance surrounding Tartary's use as a place name has spawned conspiracy theories including ideas of a "hidden past" and "mud floods". Such theories assert that Tartary (or "Tartaria") 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".