Publius Quinctilius Varus

Publius Quinctilius Varus (46 BC or before – September AD 9) was a Roman general and politician. Serving under Augustus, the founder of the Roman Empire, he is generally remembered for having lost three Roman legions in the Battle of the Teutoburg Forest and subsequently committing suicide to avoid capture (as well as execution) and shameful reproach. Varus's defeat to the Germanic tribes led by Arminius is considered to be one of the most important events in European history, as it dissuaded the Romans from further expanding into Germania and thus prevented the Romanization of the Germanic peoples to the east of the Rhine.

Source: Wikipedia — https://en.wikipedia.org/wiki/Publius_Quinctilius_Varus