Rome was the first city in history to go over a million people at its height, making it a major urban center.

Augustus, as the first emperor of Rome, established a political system that would influence countless later empires and shape global history. He oversees the transition from the Roman Republic to the Empire, setting a template that future emperors follow for the next 500 to 1500 years, as they all aspire to be like him, adopting his titles such as 'Caesar Augustus' and 'Imperator'.

The high point of the Roman Empire is often marked by the period of the five good emperors, who ruled wisely and promoted stability, contrasting with the chaotic succession that followed.

Charlemagne is crowned by the Pope on Christmas Day in 800 AD as 'Charles Augustus, Emperor of the Romans', reflecting the powerful image of Augustus that persists through history.

Rome's success can be attributed to its ability to integrate conquered peoples and ideas, often granting them a degree of Roman citizenship.

Diocletian attempted to stabilize the Roman Empire by issuing a new solid gold coin and implementing a price edict to curb inflation, though these measures had limited success.

The rise of monotheistic religions marks a significant shift in mentality, contrasting the ancient belief in multiple legitimate gods, which shaped the cultural landscape of the Roman Empire. Before 300 AD, Romans practiced a form of pagan polytheism where multiple gods were worshipped without a central religious authority, making religion an auxiliary aspect of life rather than a driving force.

The question of when the Roman Empire fell is complex, with various dates proposed, including 476 AD when Romulus Augustulus was deposed, but the Eastern Empire continued to exist long after.

The Romans were exceptional engineers, using concrete creatively to construct enduring and aesthetically pleasing buildings, such as the Pantheon, which influenced architectural design for centuries.