Psychopathia Sexualis is one of the earliest and most influential texts on human sexuality, written by Austrian psychiatrist Richard von Krafft-Ebing. It systematically categorizes a wide range of sexual behaviors, many of which were considered “deviant” at the time, including homosexuality, fetishism, sadomasochism, and necrophilia. The book is structured as a series of case studies drawn from clinical observations, legal records, and personal accounts, blending scientific analysis with moral judgment. Though initially intended as a medical text for forensic psychiatrists and legal professionals, it became widely read and had a profound influence on both early psychology and cultural attitudes toward sexuality.

Psychopathia Sexualis was banned and censored in multiple countries due to its explicit descriptions of sexual behavior, particularly those considered taboo or criminal. In the late 19th and early 20th centuries, discussing sexuality—especially homosexuality and paraphilias—was seen as obscene and morally corrupting. Some editions were heavily edited or omitted entire sections to avoid legal repercussions. Additionally, the book was later criticized for pathologizing non-heteronormative sexualities, influencing discriminatory medical and legal policies for decades. Despite this, it remains a foundational text in the study of human sexuality and the history of psychiatry.