Aurelian was a Roman emperor who ruled from 270 to 275 AD. He is best known for his military successes, which helped to reunify the Roman Empire during a time of crisis. Aurelian defeated various external threats, including the Goths and the Palmyrene Empire, restoring stability to the empire. In addition to his military achievements, Aurelian is credited with significant reforms. He restructured the empire's economy and improved its defenses, including the construction of the Aurelian Walls around Rome. His reign is often seen as a turning point that helped to strengthen the Roman Empire in the late 3rd century.