Aemilianus (Marcus Aemilius Aemilianus Augustus) was an emperor of Rome in the 3rd century AD. He ruled for 3 months in 253AD.
After defeating the Goths (a barbarian tribe) in modern-day Bulgaria, his soldiers proclaimed him as an Emperor instead of Trebonianus Gallus, the emperor at the time. After defeating Gallus in battle at Interamna (Northern Italy), he captured the capital city of the empire, Rome.
When Valerianus, Governor of Roman Germany, arrived in Italy] bringing troops to reenforce Gallus, Aemilianus' troops killed him. They did not want a civil war and Valerian had a bigger army than Aemilianus.