To the keen observer of American political and medical history, a disturbing set of debates surrounded the sanity of free Black residents of the United States of America after the publication of the controversial 1840 census returns on race and insanity. This article analyzes how the census became a battlefield where physicians and other commentators fought over—and thus shaped—various political meanings of Black insanity before and after the American Civil War, up until the 1890s, as the South underwent a massive political and social transformation, from slavery to emancipation. It also highlights the arguments raised by authors such as James McCune Smith and Ramón de la Sagra who attempted to disprove the returns shortly after their publication, and whose arguments contributed to efforts to combat scientific racism.

对于美国政治和医学史的敏锐观察者来说，在有争议的 1840 年种族和精神错乱人口普查报告公布后，围绕美国自由黑人居民的理智展开了一系列令人不安的辩论。本文分析了人口普查如何成为一个战场，在美国内战之前和之后，直到 1890 年代，随着南方经历了大规模的政治和社会变革，医生和其他评论员争夺并塑造了黑人精神错乱的各种政治含义，从奴役到解放。它还强调了 James McCune Smith 和 Ramón de la Sagra 等作者提出的论点，他们在出版后不久试图反驳这些回报，他们的论点有助于打击科学种族主义。