Quote Originally Posted by Ludens View Post
This sounds rather dodgy to me. The Romans may have given up on incorporating Germany into the Empire, but that doesn't mean they left it alone. Both Tiberius and Germanicus the Younger campaigned in Germany after the defeat at Teutoburg Forest. So did Julian the Apostate three centuries later. Remember that for the Romans the objective of military action was not necessarily conquest, but submittal. They may not have intended to subjugate Germany, they simply wanted to instil respect for the Roman Empire into its inhabitants.
Ludens is right. Tiberius himself stated that the purpose was to revenge for Teutoburg defeat, to show the Germans what the Romans could do, and to quote "revive the honor of the Roman arms" - his exact words. No Roman emperor after Augustus ever tried to subjugate Germania. They knew it was more than they could hold. Rhine River and the limes were a great defensible frontier, and Germania itself did not have such frontiers. All it had was endless forests, which Romans themselves would often cut down to lessen the chance of surprise attack (this behavior was observed everywhere, not just in Gaul or Germania). Defending conquered Germania would be too much for Roma.

Not only this, but Germania at that time was not such a tempting piece of real estate. British Isles had tin and other metals. Gaul had fertile land, metals, already developed Celtic civilization with numerous useful crafts, while Germania was very sparsely settled in comparison, with very few large settled communities.