This book covers over a century of history, from the emergence of Kurdish nationalism in the interwar period to the 2010s when, for the first time in modern history, Kurdish forces controlled two autonomous political entities in Iraq and Syria, as well as over a hundred municipalities in south-eastern Turkey. In these years of momentous advance for Kurdish forces across the region, Kurdish politics remains deeply divided into competing movements pursuing irreconcilable projects for the future of the nation. The author investigates the origins of the present divide in the history of Kurdish nationalism. The book turns the historical sociology to study nationalism as embedded in social conflicts through a comparative analysis of the history of the Kurdish movement in Iraq and Turkey, by reassessing the literature on Kurdish politics and filling its gaps with numerous interviews with witnesses and scholars.