My dissertation explores the processes of judicial, administrative, and extralegal political retribution against traitors in East Asia from 1937-1951 and the battles to define, delimit and control the bounds of treason in order to determine what role these struggles played in the reconstruction of nation in the aftermath of World War II. My project takes a comparative and transnational approach incorporating China, Korea and, in a much shorter contrastive epilogue, Japan. Through the use of representative case studies at the national, local, and historiographical level, I will attempt to show how the issue of treason came to play several highly important but often contradictory roles in the early postwar political struggles, influence competing conceptions of national identity, and build a historical narrative of the immediate past which attempted to account for the harrowing years of wartime and colonial occupation. In this way my dissertation will contribute to a growing body of research on political retribution in the aftermath of World War II in Europe, to our understanding of the huge social and political changes and conflicts in transwar and early postwar East Asia, as well as the continuing legacies of this issue in China and Korea today.