The article reconstructs attempts to create scientifically coherent, internationally agreed-upon diagnostics for mild forms of schizophrenia throughout the 20th century. A particular focus here lies on what became known as bland—or sluggish—schizophrenia, a particular term coined in the USSR, which became known for its frequent use in internationally contested diagnoses of human rights activists. The argument follows the diagnosis of sluggish schizophrenia from its inception in a highly productive and equally international psychiatric community of the early 20th century pioneered by (...) prominent Soviet scholar Andrey Snezhnevsky and through its epistemic detachment and content-related transformation in the highly isolated Soviet psychiatric community since the interwar period. This transformation is analyzed with help of the case study on the International Classification of Diseases (ICD). Released by the World Health Organization, the ICD—and in particular its ninth revision—played a crucial role in the attempt to legitimize sluggish schizophrenia. The comparative study of four presumably identical ICD-passages from three languages helps reconstructing how internationally accorded terms would become adapted to the Soviet societal and political realities. The ultimate aim of the attempted adaptation, the article claims, was to provide the elsewhere contested diagnostic term “sluggish” schizophrenia with additional legitimacy per authority of the WHO and, thus, much needed credibility for domestic, and often political, use. (shrink)