The Battle of the Teutoburg Forest, described as clades Variana (the Varian disaster) by Roman historians, took place in 9 CE, when an alliance of Germanic tribes led by Arminius of the Cherusci ambushed and decisively destroyed three Roman legions and their auxiliaries, led by Publius Quinctilius Varus.
Despite several successful campaigns and raids by the Roman army in the years after the battle, they never again attempted to conquer Germania territory east of the Rhine River.
Upon hearing of the defeat, the Emperor Augustus, according to the Roman historian Suetonius, was so shaken that he stood butting his head against the walls of his palace, repeatedly shouting: “Quintili Vare, legiones redde!“ (‘Quintilius Varus, give me back my legions!’)
The battle abruptly ended the period of triumphant Roman expansion that followed the end of the Civil Wars 40 years earlier. Augustus’ stepson Tiberius took effective control, and prepared for the continuation of the war.
Arminius sent Varus’ severed head to Maroboduus, king of the Marcomanni, the other most powerful Germanic ruler, with the offer of an anti-Roman alliance. Maroboduus declined, sending the head to Rome for burial, and remained neutral throughout the ensuing war. Only thereafter did a brief, inconclusive war break out between the two Germanic leaders