Conquest of Istanbul Day Date in the current year: May 29, 2024

The city of Istanbul was founded by Greeks in 657 BC. Its original name was Byzantium. In 330, emperor Constantine the Great relocated seat of the Eastern Roman Empire to Byzantium. He renamed it New Rome, but most people called the city Constantinople after the emperor.

In 1453, Constantinople was besieged by Ottoman forces led by Sultan Mehmed II. The city fell on May 29, 1453. After the contest, Mehmed II relocated the capital of the Ottoman Empire from Edirne to Constantinople. Contrary to popular belief, he did not officially rename it Istanbul. This name had been used before the conquest, but it was made official only in the 1930s.

The Ottoman conquest of Constantinople marked the end of the Eastern Roman Empire and the beginning of the expansion of the Ottoman Empire. This event is considered to be a turning point in Turkish history (much like the Battle of Hastings in the history of Britain). In Istanbul, the anniversary of this event is usually marked by celebratory events. This is a local holiday, it is not celebrated throughout the country.