What caused the fall of the Roman Empire

It was caused by a mix of different scenarios. Rome was constantly attacked by Barbarian tribes; they were over-expanded, which made it really hard for them to keep their entire empire under control; they had a lot of economic problems and relied too much on slave labor; and they spent way too much money on their military, just to name a few factors.

Natural disasters

Slave labor

Fast expansion of the Empire

Barbarian Invasion

Decline in Morals