The Byzantine Empire
The Byzantine Empire was the eastern half of the Roman Empire that lasted for 1,000 years after the empire collapsed. The empire existed from 330 to 1453 AD. its capital was Constantinople (modern-day Istanbul). The empire preserved laws, cultures, and traditions with influences from the Greek language and Orthodox Christianity. The Byzantine Empire lasted until 1453 AD where it fell due to the technology of cannons in a 53-day siege.
Constantine the Great
Constantine the Great founded Constantinople as the empire's capital and was the first Roman Emperor to convert to Christianity.