Battle of the Teutoburg Forest
The Battle of the Teutoburg Forest (AD 9) was a major defeat for Ancient Rome, with three legions under Publius Quinctilius Varus being destroyed. The German forces were led by Hermann (Latin: Arminius).
The Roman Emperor Augustus likely had intended to conquer the German region between the Rhine and Elbe rivers, with this being prevented by the defeat. Tacitus described Hermann as “unquestionably the liberator of Germany”.
After Augustus, the Roman borders became, with some exceptions, relatively stable.
Hermann and the Battle of the Teutoburg Forest became German nationalist symbols.
A more recent, politically correct view is that the Rhine was a better border than the Elbe, despite that using the Elbe would have shortened the Roman border and it would have been further shortened if Rome had advanced beyond the Elbe. Various resources would also have been gained by Rome.
Following World War II, Hermann became less known among West Germans and many schools shunned away from teaching the subject in any detail, due to its previous association with nationalism. The 2,000-year anniversary of the battle in Germany was celebrated with restraint, avoiding "flag-waving festivals" and other gestures that might be interpreted as nationalism.