Kang Man-Kil is the first historian to position overcoming of division and reunification of the Korean peninsula as the most important scholarly topic. The overall structure of his historiography is constructed of: first, gaining a penetrative historical perspective on the Age of National Division, and second, establishing a new historical framework that can overcome division. These two themes can be encapsulated into his term, ‘reunification nationalism’. ‘Reunification nationalism’ is the rightful guiding ideology for the Korean society, contributing to overcoming division and reunifying the nation. Kang’s reunification nationalism is meaningful in three ways: 1. It is an ‘alternative historiography’, in which the national united front movement based on negotiations between left and right wings since the colonial period is seen as the mainstream of national history. 2. It recognizes the entire Peninsula as one national unit and it is an ‘anti-divisionist historical perception’ that considers all Peninsula citizens to be agents of historical development. 3. All Peninsula citizens are seen to constitute one historical and cultural community, and it is meaningful as a ‘reunification theory’ based on peaceful, reciprocal and equitable methods. In sum, the above-mentioned three aspects of reunification nationalism form the basis of the details of Kang Man-Kil’s reunification nationalism, which is his ‘theory of equitable reunification’.