At its height, the Byzantine Empire controlled most of which of the following waterways?

The Atlantic Ocean

The Black Sea

The Dnieper River

The Northern Sea

At its height, the Byzantine Empire controlled most of the Black Sea. The capital of the empire, Constantinople, was located at the Black Sea and the Bosporus. The Bosporus connected the Black Sea and the Mediterranean Sea. The Byzantine Navy was under the rule of Justinian I, who ruled for nearly 40 years from 527 till 565, the master in the Mediterranean Sea. Constantinople was because of the central location very popular for traders from Asia and Europe.