The Eastern Roman Empire, often referred to as the Byzantine Empire, primarily bordered the Mediterranean Sea. Additionally, it had coastlines along the Aegean Sea and the Black Sea. The strategic location of these bodies of water played a vital role in trade, military strategies, and cultural exchanges during the height of the empire.
The Mediterranean Sea was crucial for naval power and allowed for the movement of goods and resources between various regions, which helped to sustain the empire’s economy. The Aegean Sea also provided vital access to the important trade routes connecting to Asia and Europe, while the Black Sea was essential for trade with the northern regions as well as protecting against invasions.