International relations theory has repeatedly failed to grasp dramatic changes occurring in East Asia. Asia has long remained peripheral, approached deductively based on findings drawn from the Euro-Atlantic region rather than through the prism of area experts and debates within the region. In this volume, experts on East Asia focus on each of the past five decades to explain the weak predictive power of traditional IR theory as applied to the region and uncover the true forces driving change. While recognizing that realist and liberal theories have vied for preeminence in recent decades, this book showcases the rise of constructivist (national identity) theory. Gilbert Rozman's chapters on each decade cover theoretical issues including strategic triangles, rising powers, regionalism, and Eastern vs. Western civilization. Contributors also examine other triangles, bilateral relations, and views of theory within the region. Parallel chapters explore historical legacies of growing relevance in China, Japan, and Russia in the 2010s, and the Korean Peninsula figures heavily throughout as a challenge to theory.