Answer:
1. Nomadic invaders sacked and destroyed property within the empire.
2. New religions replaced those of the people in the empire.
Step-by-step explanation:
There were many attempts of invasion coming from Germanic tribes while Buddhism also spread through Hans Empire.
Roman Empire was so powerful that it lasted for more than 500 years. Among other reasons like taxes, the Roman Empire officially fell because of the invasions of Germanic Nomadic tribes. A similar thing has happened to the Han dynasty which was invaded by the tribe which later evolved into the Hun clan. The Gupta Empire was attacked by the White Huna tribe, but the biggest reason for the fall of the Gupta Empire is the corruption of people in the empire.
The second logical reason for the fall of the Roman Empire is Christianity.