In 324, Constantine I chose Byzantium to be the new capital of the Roman Empire, renaming it New Rome. Following the death of Theodosius I in 395 and the permanent division of the Roman Empire between his two sons, the city, which would popularly come to be known as Constantinople, became the capital of the Eastern Roman Empire. This empire, which would later be branded by historians as the Byzantine Empire, ruled most of the territory of present-day Turkey until the Late Middle Ages; although the eastern regions remained firmly in Sasanian hands until the first half of the 7th century CE. The frequent Byzantine-Sassanid Wars, a continuation of the centuries-long Roman-Persian Wars, took place in various parts of present-day Turkey between the 4th and 7th centuries CE.