Reddit reviews Fall of the Roman Empire, The

I don't mean to be that guy, but...

You can trace the barbarian attacks on Rome to the mass migration caused by the invasion of Europe by the Hun. This resulted in many of these Germanic tribes relocating to Rome's borders.

Peter Heather, an Oxford Historian, wrote a fascinating book called The Fall of the Roman Empire, and he goes into great detail in how this mismanagement of the migrant crises was a major contributing factor to the downfall of the Roman Empire.

I await downvotes.