In the twentieth century, Taiwan and Korea shared similar experiences of colonial governance: from being situated on the periphery of the Qing geocultural orbit and the early frontiers of the Japanese Empire to becoming a Cold War protectorate of US neoimperialism. This special issue draws on theoretically robust and empirically weighted approaches to examine this shared but contested past. Though the respective histories of medicine in postcolonial Taiwan and Korea have become vibrant sites of scholarly dialogue, there has been no sustained effort to bridge them or bring them together in a unifying, comparative, and critical frame. This special issue takes a bold step in that direction without claiming exhaustive or exceptional coverage. Featuring articles authored by an international and interdisciplinary cohort of scholars, this issue of EASTS explores the cultural transformations of medicine, health, and the body in light of such unique trajectories of political affinity and potential divergences. Although contributors mainly focus on their geographical area of expertise rather than elaborating on specific historicities that emerge beyond those regional parameters, the diversity of topics, chronologies, archives, and theoretical frameworks sampled in this issue offers a rare occasion to reflect collectively on the historiographical stakes of what makes the politics of Taiwan-Korea comparison meaningful.