Emperor Constantine the Great announces free distributions of food to the citizens in Constantinople.

Constantine I, also known as Constantine the Great, was a Roman emperor from AD 306 to 337 and the first Roman emperor to convert to Christianity. He played a pivotal role in elevating the status of Christianity in Rome, decriminalising Christian practice and ceasing Christian persecution. This was a turning point in the Christianisation of the Roman Empire. He founded the city of Constantinople and made it the capital of the Empire, which it remained for over a millennium.

Constantinople was a historical city located on the Bosporus that served as the capital of the Roman, Byzantine, Latin and Ottoman empires between its consecration in 330 and 1930, when it was renamed Istanbul. Initially as New Rome, Constantinople was founded in 324 during the reign of Constantine the Great on the site of the existing settlement of Byzantium and in 330 became the capital of the Roman Empire. Following the collapse of the Western Roman Empire in the late 5th century, Constantinople remained the capital of the Eastern Roman Empire, the Latin Empire (1204–1261) and the Ottoman Empire (1453–1922). Following the Turkish War of Independence, the Turkish capital moved to Ankara. Although the city had been known as Istanbul since 1453, it was officially renamed Istanbul on 28 March 1930. The city is today the largest city in Europe, straddling the Bosporus strait and lying in both Europe and Asia, and the financial center of Turkey.

May 18 is the 138th day of the year in the Gregorian calendar; 227 days remain until the end of the year.