Ottoman Empire

Timeline

1. 1451Edirne · ThraceAfter the death of Sultan Murad II, his son Mehmed II acceded to the throne for a second time at only 19, immediately renewing peace treaties with Byzantium, Hungary, and other neighbors to stabilize the frontiers while secretly planning the campaign against Constantinople, building the Rumeli Hisarı fortress on the European shore of the Bosphorus to cut the city's supply lines; the empire entered a new phase of active expansion.
2. 1453Constantinople · Turkish Straits regionAfter a siege of about 53 days, Ottoman forces breached the city's defenses on May 29, 1453; the last Byzantine emperor, Constantine XI Palaiologos, fell in battle, and the thousand-year Eastern Roman Empire came to an end. Constantinople was renamed Istanbul and made the new capital; Mehmed II went down in history as 'the Conqueror,' and the Ottoman Empire established its dominance over the eastern Mediterranean.
3. 1454–1460Balkan Peninsula · BalkansFrom 1454 onward, Mehmed II campaigned repeatedly in the Balkans: he annexed most of Serbia (1455–1456), was checked at Belgrade by the defeat of the Hungarian general John Hunyadi (1456), and completed the conquest of the Despotate of Morea in 1460; the last Byzantine imperial family fled to Western Europe, the whole Greek peninsula was incorporated into Ottoman territory, and the Ottomans formally became the ruling power of the Balkan Peninsula.
4. 1453–1460Istanbul · TurkeyAfter establishing Istanbul as the capital, Mehmed II carried out large-scale administrative reforms: promulgating the Kanunname (Imperial Law Code), unifying the military fief (timar) system, introducing the devşirme palace slave-soldier system to counterbalance the old nobility, and recruiting Greek, Armenian, and Jewish merchants to rebuild the urban economy, laying the institutional foundation for two further centuries of Ottoman expansion.