<onlyinclude>Ancient Rome was an Italic civilization that began on the Italian Peninsula as early as the 8th century BC. Located along the Mediterranean Sea and centered on the city of Rome, it expanded to become one of the largest empires in the ancient world with an estimated 50 to 90 million inhabitants (roughly 20% of the world's population) and covering 6.5 million square kilometers (2.5 million sq mi) during its height between the first and second centuries AD.

State of Rome (Roman State) refers to Ancient Rome as a nation-state, that is, a country. As a result, a free-born person in Syria could be considered a Roman by virtue of his citizenship although he was born nowhere near the city of Rome. Furthermore, the capital of the Roman state was not always the city of Rome. For example, the capital was moved to New Rome in the later stages of the Roman Empire, and after death of emperor Theodosius I, the capital of Western half was Mediolanum, but later Ravenna.