The city of Constantinople (modern Istanbul) was founded by Roman emperor Constantine I in 324 CE and it acted as the capital of the Eastern Roman Empire, or Byzantine Empire as it has later become known, for well over 1. 000 years. Although the city suffered many attacks, prolonged sieges, internal rebellions, and even a period of occupation in the 13th century CE by the Fourth Crusaders, its legendary defences were the most formidable in both the ancient and medieval worlds. It could not, though, resist the mighty cannons of the Ottoman Sultan Mehmed II, and Constantinople, jewel and bastion of Christendom, was conquered, smashed, and looted on Tuesday, 29 May 1453 CE.