Constantinople
Constantinople (; ) was the capital city of the Roman/Byzantine Empire (330–1204 and 1261–1453), and also of the brief Crusader state known as the Latin Empire (1204–1261), until finally falling to the Ottoman Empire (1453–1923). It was reinaugurated in 324 from ancient Byzantium as the new capital of the Roman Empire by Emperor Constantine the Great, after whom it was named, and dedicated on 11 May 330. The city was located in what is now the European side and the core of modern Istanbul.
History of Europe
In the 4th century, the emperors Diocletian and Constantine were able to slow down the process of decline by splitting the empire into a Western part with a capital in Rome and an Eastern part with the capital in Byzantium, or Constantinople (now Istanbul). Whereas Diocletian severely persecuted Christianity, Constantine declared an official end to state-sponsored persecution of Christians in 313 with the Edict of Milan, thus setting the stage for the Church to become the state church of the Roman Empire in about 380.