ConstantinopleConstantinople - By the 4th century, the Roman Empire, particularly the west, was in steep decline. It likely would have collapsed even sooner than it did had Constantine not taken measures to extend its life. The most significant geographical change he made was to move the capital east to the Greek city of Byzantium. Most of the empire's wealth was in the east, and by Constantine's time, the west was becoming a drag by consuming a disproportionate amount of resources. He wanted to move the seat of government to where it could readily exploit those resources. Not realizing it at the time, Constantine also increased the capital's security. The barbarian invasions which began a half century later would eventually bring about an end to the Roman Empire in the west. By contrast, the peninsula on which Byzantium rested was highly defensible. Surrounded on three sides by water, only its western border was accessible by land. A massive wall built along this border made the city practically impregnable. Constantine's embrace of Christianity also must have played a role in his decision to move the empire's capital. Rome was a pagan city, full of pagan temples, and Byzantium offered him a fresh opportunity to build the new city with a strong Christian influence. A number of churches and basilicas were built, culminating in the Hagia Sophia in the 6th century (see Hagia Sophia), and the city eventually became a cultural centre for Christianity.


In addition to all these, Byzantium offered several economic benefits as the empire's capital. Located on an isthmus known as the Bosphorus, it allowed easy access to both the Black and Mediterranean Seas. Off of the Bosphorus, ran in inlet along the city's northern edge known as the Golden Horn. This created one of the best natural harbors of any city in the entire empire. To the west, ran the Danube River which allowed traders to easily penetrate the interior of Europe. The Euphrates to the east allowed the same in Asia. The transition to the new city began in 324, the same year Constantine defeated Lucinius, and was completed by 330. He named it Nova Roma (New Rome), but locals called it Konstantinoupolis (Greek for "City of Constantine), which was Latinized into Constantinople. However, the legacy of the city's original name survived as the Eastern Roman Empire would come to be known as the Byzantine Empire. The final schism between the eastern and western halves of the empire took place in the late 4th century when Emperor Theodosius' sons, Acadius and Honorius, each claimed a half as their own. Of course, today the city is known as Istanbul, as it was renamed by the Ottomans who conquered it in 1453.