When did the name of Istanbul change? Let's correct the misunderstandings that you know to be true. When did Istanbul get this name?
There is a perception as if the name of the city changed from Constantinople or Constantinople to Istanbul after the conquest in 1453. This is absolutely false information.
After the conquest of Istanbul, the city continued to be called Constantinople or Constantinople for centuries. In addition, the famous historian Prof. Dr. İlber Ortaylı also confirms this information. Until the Republican period, the city continued to be called Konstantiniyye. In fact, we can see this in many Ottoman sources. Two common names for the city, Constantinople or Konstantiniyye, mean "the city of Constantine." The word Istanbul also comes from Greek. Istanbul, which is a combination of the words Stan and Polis, actually means "I'm going to the city".
The Republic of Turkey officially changed the name of Constantinople or Konstantiniyye to Istanbul in 1929. When Ankara was declared the capital of the Turkish Republic on October 29, 1923, Istanbul lost its capital status, which it had maintained since 330, that is, for 1600 years.