The Roman Empire was the post-Republican period of ancient Rome. As a polity, it included large territorial holdings around the Mediterranean Sea in Europe, Northern Africa, and Western Asia ruled by emperors.
Founded by Augustus Caesar in 31BC when he proclaimed himself as the first emperor, the Roman emperor saw more than 70 emperors in his time. The Roman Empire fell with the fall of Romulus Augustus in 476 AD.
Over the years, the Romans were able to capture land and defeat armies thanks to their superior army and battle tactics. The three most important military tactics used by Romans include the testudo, or the tortoise formation, the triple line, and innovation on the Greek phalanx, and the wedge.
The Roman Army was a highly effective war machine that constantly adapted and evolved in order to defeat new rivals and conquer new territories, ensuring Rome remained the dominant superpower for many centuries.