The Roman and Greek civilizations were two of the most influential cultures in ancient history. The Greeks are known for their contributions to philosophy, art, and democracy, with notable figures like Socrates, Plato, and Aristotle. Their city-states, such as Athens and Sparta, played significant roles in shaping political thought and cultural practices. The Romans built upon Greek foundations, expanding their influence through military conquests and engineering marvels like aqueducts and roads. They developed a complex legal system and governance structure, exemplified by the Roman Republic and later the Roman Empire. Key figures include Julius Caesar and Augustus.