According to Strabo, Istanbul is thought to have been founded by the colonists from Megara led by Byzas in the 7C BC. The popular legend has it that Megarians, before coming here, went to the oracle in Delphi and asked his instruction about the place to found their settlement. The answer was “opposite the city of the blind”. When they came to the peninsula of the old city, after seeing an earlier settlement in the Asian side, they concluded that these people must be blind not to see such a beautiful place here on this side. And remembering the words of the Delphic oracle, they founded their city “Byzantium” which derived from their leader’s name “Byzas”.
Over the next thousand years, Byzantium became a trade and commerce center. But despite great prosperity, Byzantium never distinguished itself culturally, as did so many contemporary cities in Anatolia.

In 324 AD, Constantine I defeated Licinius and became sole ruler of the Roman Empire. He also began to build a new capital at Byzantium, later named Constantinople (Constantine’s polis or city).

In 330 AD, Christianity was declared the official religion of the Roman Empire and Constantinople was dedicated as capital of the Byzantine Empire and splendidly rebuilt by Constantine I.

Constantinople itself was not only the new capital of the Empire but also the symbol of the Christian triumph.

Istanbul is famous as one of the most often besieged cities in the world. Before it was conquered by the Turks, its assailants included the Persian Darius (513 BC), the Athenian Alcibiades (408 BC), the Macedonian Philip II (339 BC), the Arabs (673-78, 717-18 AD), the Bulgarians (813, 913 AD) and the armies of the Fourth Crusade, which twice succeeded in taking the city (1203, 1204 AD). After Constantinople was taken by the Turks in 1453, the city became the capital of the Ottoman Empire until 1923, when the newly founded Turkish Republic declared Ankara (then Angora) the capital. From 1918 until 1923 Great Britain, France and Italy occupied the city.

Under the Ottomans, the city went through several name changes, among them Konstantiniyye, Polis, Stimpol, Estanbul, Istambol and Istanbul. The name was officially changed to Istanbul in 1930.

Conquest of Constantinople

Turks had already tried to conquer Constantinople four times until Mehmet II. After becoming sultan, Mehmet II immediately built the Rumeli Fortress and restored the Anadolu Fortress in order to prevent the passage of any reinforcements through the Bosphorus.

Preparations, which took two years, included enhancing the fleet and manufacturing cannons.

In April 1453, an army of 200,000 soldiers and a fleet of 400 ships were ready in front of Constantinople. In the meantime, the Byzantines blocked the entrance of the Golden Horn by stretching chains across it. The walls of Constantinople were supported with more soldiers. The main intention of the emperor was, in case of attack, to gain time with an expectation of help from the western world.

The siege started on April 6 and continued unexpectedly. Mehmet II, to the surprise of the Byzantines, took his ships to the Golden Horn over a hill near Tophane by pulling them with animal and human power on oily wood pieces. A siege of 53 days ended on May 29, 1453. Mehmet II ceremoniously entered the city and this considerable victory gave him the title Fatih “conqueror” in the Islamic world.

The tolerance of the Ottoman Turks has meant that a majority of religious buildings from the Byzantine period still exist, if only as churches converted to mosques. Compared to many other countries where these kinds of buildings were generally destroyed, it should be noted that religious tolerance was not a new tradition in Anatolian civilizations.