Ancient Roman history spans over a thousand years, beginning with the founding of Rome in 753 BCE. Initially a small settlement, it grew into a powerful city-state and eventually expanded into a vast empire that controlled much of Europe, North Africa, and parts of Asia. The Roman Republic was established in 509 BCE, leading to significant political and military developments. The transition from Republic to Empire occurred in 27 BCE when Julius Caesar's adopted heir, Augustus, became the first emperor. The empire reached its peak in the 2nd century CE, known as the Pax Romana, a period of relative peace and prosperity. However, internal strife and external pressures led to its decline, culminating in the fall of the Western Roman Empire in 476 CE.