The Roman Empire, led by emperors, spanned 27 BC to 117 AD. Augustus, its founder, marked the end of the Roman Republic. Initiating the Pax Romana, he expanded across Europe, Africa, and Asia. Governance was autocratic, with bureaucracy, legal codification, and Senate decline. The military, known for disciplined legions, conquered territories like Carthage and provinces across continents. Culturally, achievements included iconic architecture (Colosseum, aqueducts), notable literature (Virgil, Tacitus), and advanced engineering (road network). Latin became the dominant language. Yet, the empire declined in the 3rd-5th centuries due to economic instability, currency issues, invasions by barbarians, and political chaos. Diocletian's reforms split it into Western and Eastern Roman Empires. The Western Empire fell in 476 AD to Odoacer, its traditional end.