Who change the name constantinople?

Answer 1

With the conquest of Constantinople by the Ottoman Turks in 154. the name Constantinople was not dropped. During the period of the Ottoman Empire both Constantinople and Istanbul seem to have been in usage until the 19th century. Constantinople was given as Kostantiniyye, a calque (loan translation) used in the Muslim world.

Kostantiniyye appeared as the place of provenance of documents of the court and the chancellery and on coins up to the 17th century and reappeared on coins in the 19th century. The name Istanbul was associated with the highest magistrate (Istanbul efendis) and the highest military commander (Istanbul agasi). Istanbul was also the common speech name.

With the deposition of the Ottoman sultans and establishment of the Turkish Republic in 1923 Istanbul became the sole name of the city. With the Turkish Postal Service Law of 1930 Istanbul became the official name and foreigners were requested to adopt this name in their languages and drop other names. In Europe the use of the name Constantinople had remained widespread. The Turkish postal services would no longer deliver mail sent to Constantinople instead of Istanbul.

The name Istanbul is derived from the Greek word istimbolin which means in/to the city and was used to indicate Constantinople, which was often just called the City. It was already in use by the Armenians, Arabs and Turks in common speech before the conquest of Constantinople.

Answer 2

Constantine named the city of Constantinople.