Definition: Rewrite each original sentence in order to make it easier to understand by non-native speakers of English. You can do so by replacing complex words with simpler synonyms (i.e. paraphrasing), deleting unimportant information (i.e. compression), and/or splitting a long complex sentence into several simpler ones. The final simplified sentences need to be grammatical, fluent, and retain the main ideas of their original counterparts without altering their meanings.
Input: The city is what later evolved to be the center of the Byzantine Empire (the Greek-speaking Roman Empire of late Antiquity and the Middle Ages) under the name of Constantinople.

The city later became the center of the Byzantine Empire. That was the Greek-speaking Roman Empire of late Antiquity and the Middle Ages. It was Constantinople.