roman empire collapsed from wokeness. first wave was christianity killing their taste for strength and dominance. second wave was getting dependent on foreigners to do the strength & dominance job in their place, which rapidly spiraled in having to give roman citizenship to everyone. at that point, rome was no more an empire, and just a really badly defended city with a lot of riches in the middle of people who had a lot of grudges to solve with them. germanic tribes weren't the killer, just the first carrion to feed.
France