What era did rome become an empire?

The Roman Empire was founded when Augustus Caesar proclaimed himself the first emperor of Rome in 31BC and came to an end with the fall of Constantinople in 1453CE. An empire is a political system in which a group of people are ruled by a single individual, an emperor or empress. The Roman Republic became the Roman Empire in 27 BCE when Julius Caesar's adopted son, best known as Augustus, became the ruler of Rome. Augustus established an autocratic form of government, where he was the sole ruler and made all important decisions.

Explanation:

27BC-476AD IS when what you want. It is your answer