There is some debate over whether the modern Republic of Turkey is a continuing state to the Ottoman Empire or a successor.[13] The two entities fought on opposing sides in the Turkish War of Independence (1919–23), and even briefly co-existed as separate administrative units (whilst at war with one another): Turkey with its capital in Ankara and the Ottoman Empire from Istanbul, but this type of scenario is also common in civil wars. The nationalist faction, led by Mustafa Kemal who defected from the Ottoman army, established the modern republic as a nation state (or new government regime) by defeating the opposing elements in the independence war.