So far historians believed that the battle of the Teutoburg Forest, which took place in 9 AD, resulted in the Roman’s Empire withdrawal from Germania without any further attempt to conquer the land beyond the Rhine River again. But the unearthing of the battleground near the village of Kalefeld proves that Rome didn't give up its expansionary ambitions until much later than previously assumed.
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.