Arminius (also Armin, 18 BC/17 BC – 21 AD) was a chieftain of the Cherusci who defeated a Roman army in the Battle of the Teutoburg Forest. His tribal coalition against the Roman Empire successfully blocked the efforts of Germanicus, nephew of Emperor Tiberius, to reconquer the Germanic territories east of the Rhine, although there is debate among historians about the outcome of several inconclusive battles (Tacitus, Annals 2.22, Suetonius, Caligula 1.4). And although Arminius was ultimately unsuccessful in forging unity among the Germanic tribes, his upset victory had a far-reaching effect on the subsequent history of both the ancient Germanic tribes, of the Roman Empire, and ultimately, of Europe.
Around the year 4 AD, Arminius assumed command of a Cheruscan detachment of Roman auxiliary forces, probably fighting in the Pannonian wars on the Balkan peninsula. He returned to northern Germania in 7/8 AD, where the Roman Empire had established secure control of the territories just east of the Rhine, along the Lippe and Main rivers, and now sought to extend its hegemony eastward towards the Weser and Elbe rivers, under Publius Quinctilius Varus, a high-ranking administrative official appointed by Augustus as governor. Arminius soon began plotting to unite various Germanic tribes and to thwart Roman efforts to incorporate their territories into the empire.
In the fall of 9, in the Battle of the Teutoburg Forest, Arminius, then twenty-five years old, and his alliance of Germanic tribes (Cherusci, Marsi, Chatti , Bructeri , Chauci and Sicambri) ambushed and annihilated a Roman army (comprising the 17th, 18th and 19th legions as well as three cavalry detachments and six cohorts of auxiliaries) totalling around 20,000 men commanded by Varus. Recent archaeological finds suggest that the long-debated precise location of the three-day battle is almost certainly near Kalkriese Hill, about 20 km north of Osnabrück. When defeat was certain, Varus committed suicide by falling upon his sword.</i></sub>
Hermannsdenkmal near Detmold, Germany