The Byzantine Empire, also referred to as the Eastern Roman Empire, was the continuation of the Roman Empire in the East during Late Antiquity and the Middle Ages, when its capital city was Constantinople (modern-day Istanbul). It survived the fall of the Western Roman Empire in the 5th century AD and continued to exist for an additional thousand years until it fell to the Ottoman Turks in 1453. The borders of the Empire evolved significantly over its existence. During the reign of Justinian I (527–565 AD), the Empire reached its greatest extent after reconquering much of the historically Roman western Mediterranean coast, including North Africa, Italy, and Rome itself. During the reign of Maurice (582–602 AD), the Empire’s eastern frontier was expanded. However, his assassination caused the Byzantine–Sasanian War of 602–628, which exhausted the Empire’s resources and contributed to major territorial losses during the Early Muslim conquests of the seventh century. In a matter of years the Empire lost its richest provinces, Egypt and Syria, to the Arabs.