Answer :
The city that the Ottoman Empire chose for its capital was Constantinople, which is now known as Istanbul.
The answer is Constantinople.
In 1453, Sultan Mehmed II, "The Conqueror" of the Ottoman Empire, attacked and conquered the capital's city of Roman/Byzantine Empire: Constantinople. One of the first things he did was to choose the city as his new capital, an Islamic one. He also turned Hagia Sophia (the main Greek cathedral) into a Turkish mosque, as well as many others, he initiated reconstruction projects for Constantinople and took several actions to re-populate it.
