The Roman Empire fell because the Germanics got stronger and conquered them - the North got more and more powerful and populated. That's it - plus empires decline. I'm sick and tired of people denying human agency for this era. If there wasn't these external forces, driven *by individuals* then the Christian Western Roman Empire would endure forever into modernity like China. Stagnant, filled with internal contradictions, collapsing in on itself every now and again, but eternally surviving because of a lack of opposition (that didn't just assimilate).

>>17862058 (OP)
Various germanic groups were pretty much the backbone of the Roman armies too, defending the Empire (or the successor kingdoms) from actual non-European threats like the Huns.