Originally Posted by Ambiorix

No, the Roman empire was at its greatest under Augustus.

I voted for Cicero though. Julius Caesar ironically enough -and in part- destroyed Rome's future by setting all the tables for an empire. (other's like Marius and Sulla proceeded him by making the army a mercenary army, but Caesar was started the era of emperors). Empires are great during the life of a great emperor, but they usually crumble and fall under weaker successors.