 The major defeat of the Battle of Barbalissos was very costly for the Roman emperor Valerian who appointed many more armies to stop Shapur I from quick advance into Roman soil and later on he decided to lead a major army of 70,000 legionaries himself.For 1,000 years, the Roman Empire was a major power in Europe.Roman emperors controlled most of Southern Europe, North Africa, and some parts of Asia giving them the numbers to encounter any intruding forces.