Battle of the Teutoburg Forest

The Battle of the Teutoburg Forest, also called the Varus Disaster or Varian Disaster (Latin: Clades Variana) by Roman historians, was a major battle fought between an alliance of Germanic peoples and the Roman Empire between 8 and 11 September 9 CE, possibly near modern Kalkriese. Fighting began with an ambush by the Germanic alliance on three Roman legions being led by Publius Quinctilius Varus and their auxiliaries; the alliance was led by Arminius, a Germanic chieftain and officer of Varus's auxilia.

Source: Wikipedia — Battle of the Teutoburg Forest (CC BY-SA 4.0)