The attacking Ottoman army, which significantly outnumbered Constantinople's defenders, was commanded by the 21-year-old Sultan Mehmed II (later called "the Conqueror"), while the Byzantine army was led by Emperor Constantine XI Palaiologos. After conquering the city, Mehmed II made Constantinople the new Ottoman capital, replacing Adrianople. The Fall of Constantinople marked the end of the Byzantine Empire, and effectively the end of the Roman Empire, a state which dated back to 27 BC and lasted nearly 1,500 years. The capture of Constantinople, a city which marked the divide between Europe and Asia Minor, also allowed the Ottomans to more effectively invade mainland Europe, eventually leading to Ottoman control of much of the Balkan peninsula.