In a scenario where the Ottoman Empire never existed (say Osman died before he could become leader of the Turkish group which became the Ottomans or his group got wiped out early on), how would Anatolia develop? Could any other Turkish beyliks have filled the role of the Ottoman Empire? Could Byzantium/Rhomania have hung on longer than it did historically in a world without the Ottoman Empire? What happens to the Middle East? How does the Mamluk Sultanate develop?