When did Rome think it was important/necessary to have an emperor?

The Romans thought that it was important to have an emperor when there were provincial conflicts and wars along the frontiers.

Explanation:

Before becoming an empire, Rome was a Republic which was founded in 509 BCE. Rome represented a republic democracy and most of the wealthy families held power and the major offices in Rome. With the expansion of the territory and power of the Roman Republic, internal conflicts emerged when the citizens and the wealthy families struggled for power. Eventually civil wars broke out in the region and the people though that it was essential to have an emperor who would hold most of the power.