Caput Mundi

Roma Caput Mundi is a Latin phrase taken to mean "Roma capital of the world" (literally: "head of the world"; see , ). It originates out of a classical European understanding of the known world: Europe, North Africa, and Southwest Asia.

The influence of Rome in the ancient world began to grow around the 2nd century BC as the Republic expanded across Southern Europe and North Africa. For the next five centuries, Rome would govern much of the known world (of traditional Greco-Roman geography). The cultural influence of the local language of Rome (Latin) as well as Roman art, architecture, law, religion and philosophy was immense. The city of Rome adopted as its nickname Caput Mundi, attributing this to its perception of an enduring power of Ancient Rome and the Roman Catholic Church.

Constantinople was built as the second Rome by Emperor Constantine in 330 AD.

The Byzantine Empire lasted for over a thousand years with the center always at Constantinople, except between 1204 and 1261, when it was centered in the capitals of Nicaea, Trebizond, and Arta. The city was seen as the "Capital of the World" because of its prime trading position in the center of the medieval world. This privileged position continued even as the capital of the Ottoman Empire. The city was also the center of half of the Christian world as the seat of the Patriarch of the Eastern Orthodox church. Napoleon Bonaparte is quoted as saying, "If the Earth were a single state, Constantinople would be its capital." Today, the city's name is Istanbul.

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