This book explores the historical writings of postwar Japanese Marxists - who were, and who continue to be, surprisingly numerous in the Japanese academic world. It shows how they developed in their historical writing ideas of "radical nationalism", which accepted presupposed ideas of Japan's "ethnic homogeneity", but which they saw as a "revolutionary subject", creating a sphere of radical political action against the state, the American Occupation and global capital. It compares this approach in both prewar and postwar Marxist historiography, showing that in the postwar period ideas were more elaborate, and put much more emphasis on national education and social mobilization. It also shows how these early postwar discourses have made their way into contemporary ethnic nationalism and revisionism in Japan today. The book's rich and interesting analysis will appeal not just to historians of Japan, but also to those interested in nationalism and Marxism more generally.