Mehmet II was the victorious leader during the fall of Constantinople. He was the Sultan of the Ottomans. Constantinople was the capital of the Eastern Roman Empire. After the winning of the war Constantinople it was renamed as Istanbul by Mehmet II. After the conquering of Constantinople there was nothing to stand between Mehmet II and Europe. Christianity was dealt a big blow. After Constantinople was captured, many Greek nobles had no other option but to flee and take refuge in countries like Italy.