Answer: The city was a symbol of Christian fame and power.
Step-by-step explanation:
Byzantium survived for centuries after the fall of the Western Roman Empire. Mehmed II knew that Constantinople was a symbol of Christian power and strength. For this reason, he wanted to conquer the city and show the world that the Ottoman Empire was the most powerful power at the time. Constantinople was also an important geostrategic and trading place, and for these reasons, the Ottoman capital just became Constantinople.