Kalkriese

Historians still point to this as one of the reasons Roman law and culture took root so deeply in Gaul and Spain, Latin included, while the regions east of the Rhine developed along an entirely different path, a divide that arguably still echoes in the linguistic and cultural map of Europe today.

For centuries, historians could only guess at exactly where the battle had happened, and it wasn't until the 80s and 90s that archaeologists uncovered convincing physical evidence, weapons and coins, along with human remains, at a site called Kalkriese, near modern Osnabrück in Germany, now widely believed to be at least part of the battlefield.

And Germanicus' story gives us the human through line that connects Augustus' original ambition, the disaster that ended it, and the caution that defined everything that came after.

It's a big part of the reason Augustus and the emperors who followed him increasingly favored consolidation over conquest, a theme that, if you keep listening to this series, you'll see running right through Tiberius' cautious governance and later becomes the entire philosophy behind Hadrian and his wall.