Invasions of people--many of the groups came as military and fought the Romans as invading forces.
Counterclaim--they were migration patterns as they were attempting to gain access to an empire with advanced trade and education. Migrating to the Roman Empire gave a person or group with extra resources.
The natural disaster is EARTHQUAKE.
On the 8th of October, 2005, the Kashmir region of India and some sections of Pakistan and Afghanistan was hit by an earthquake. The earthquake had a magnitude of 7.6. The earthquake caused a lot of damages and a huge number of people lost their lives during the event, many more become homeless.
Death from diseases, lack of food, like each other.
