What happened in the Teutoburg forest?

The Teutoburg Forest went down in history thanks to the battle between the Romans and the Germans in September 9 AD. One of the few events related to the first decade of the new era. The Romans were defeated.

Now this place is located in Lower Saxony (administrative unit in the Federal Republic of Germany).

The Roman army was led by Publius Quintilius Varus. Or simply Var, he was the governor of the province of Germany. His army probably numbered about 12-18 thousand legionnaires, and the number of the army of his enemy, the German Arminius, is unknown, since the Germans did not have written sources, and the Romans had chronicles and the army was divided into legions.