According to Tacitus's Germania, Tuisto is the legendary divine ancestor of the Germanic peoples. The figure remains the subject of some scholarly discussion, largely focused upon etymological connections and comparisons to figures in later Germanic mythology.

The Germania, written by the Roman historian Publius Cornelius Tacitus around 98 AD and originally entitled On the Origin and Situation of the Germans, is a historical and ethnographic work on the Germanic peoples outside the Roman Empire.