In the year 200 A.D. a huge crisis shattered Rome and left them devastated. The whole Roman Empire was devastated. Because most of the leaders died and the military took almost complete control.
Diocletian
The Diocletian forced the Roman society into rigid order. All aspects of life were under imperial administration. Diocletian said sons follow fathers in trade and social position and peasants stay tied to farm land
Constantine
After the death of Diocletian, Constantine took over. He kept the same rules as Diocletian but he did something no one else ever did.
Rome
When Constantine took over he split Rome completely in half. He made the eastern half rich and much better defended than its partnering western half.
Invaders
Some people began to move in. This in return pushed the invaders closer to Rome. This eventually began to make Rome fall apart and crumble.
Huns
When Rome split in half The Huns became the new rulers of the western half of the Roman Empire. The Huns being the rulers of the western half eventually lead to the cause of the whole empire falling. Therefore the Huns were partly the cause of the Fall of Rome.