The Battle of Germania

It was only the timely intervention of Herod Agrippa that prevented a massive uprising against the Romans. Had Herod not been there to talk some sense into Caligula, the Revoltan Judea almost certainly would have erupted 30 years earlier than it eventually did. Having become a god though, there was still something conspicuously absent from Caligula's resume - military conquest. Being an imporator without any military triumphs to point to, it was like being a surgeon who has never performed surgery, just doesn't make sense on the face of it.