That map is just awsome in so many ways. Where is Denmark and Sweden though? Romans just didn't think there was anything up there? Nothing? Way too cold up there for people to live?
Presumably also because there wasn't much there at the time that would've allowed them to collect taxes.
> Presumably also because there wasn't much there at the time that would've allowed them to collect taxes. The Romans liked to portray Germania as poor and inhospitable. Part of the reason for that could be cognitive dissonance for never having conquered it.
Half of Cesar's Gallic War seems to be more than half about grain logistics (huge efforts to start the campaigns jus a few weeks earlier) and ripeness of the local crops. And that is even while he was likely trying to downplay all the robbery.
Production beyond the Rhine simply was not great even in times of peace, before the middle ages. Rome ended up controlling most of the German territory through client states anyway, even sending troops for punitive raids and propping up this or that friendly ruler, so they knew the economic potential of those lands pretty well; they just renounced full invasion because it was not worth the risk. At a time when they were already hitting what we could call scaling limits in their ability to mobilise troops over long distances, there was little appetite for going further North, where clearly there were no riches waiting for them. A similar assessment was done for Scotland, and rightly so.
This went on for many generations, it's not a "last days before the ostrogoths" exception. Competing "emperor startups" in an empire representing pretty much the entire known civilized world, surrounded by mostly harmless outlaw wilderness. It must have felt as natural and "could the world even be not like this?" to the people populating that world as nation states, competing militarily, economically and in the Olympics seem natural to us.
Allow me to apologize for my lack of precision, I never intend to imply that they deliberately avoided "invader-friendly" crops. Wheat just had not spread that far, due to climate (not yet sufficiently adapted by breeding?) and/or cultural reasons: nomadism (well, more effect than cause I guess) and the fact that large scale forest clearances are the type of project that can only happen in presence of big organizations that are stable enough to enable such long term investments. Many German settlements still carry the name of the medieval nobleman who commissioned the original clearance (names ending in -rode, -roda, -reuth and probably some more regional variations), which implies that before the clearance, there was only wilderness.
An abbreviated version may be found in https://www.youtube.com/watch?v=eS5Asjvhx6I :)