Explanation: The Third Century AD included a ~50 year period known as the Crisis of the Third Century. Disease, economic disruption, civil war, political instability, religious upheaval, and barbarian invasions all came together to form one, Empire-destroying mass. The Roman Empire eked out of the crisis (really a series of horrific events, like the Empire splitting into three, or having five civil wars in five years) just barely intact - but the damage would reverberate until the Empire's fall. There was no recovering from the Crisis of the Third Century.