Constantinople
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. Thus as the world center for commerce, diplomacy, religion, education, it could well have been said that during the city's heyday, Constantinople was indeed the capital of the world. 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.
Read more about this topic: Caput Mundi