de:Franz Vältl, photographer, Weimar · Public domain

An Austrian physician among Freud's earliest followers, credited by Ernest Jones with founding, alongside Freud, the first psychoanalytic society. He had a genuine talent for detecting repressed material in patients and helped popularize psychoanalysis in its formative years. He and Freud later broke over personal rather than theoretical differences — Freud wrote that it was Stekel's character and conduct, not scientific disagreement, that made collaboration impossible — but Stekel's writings continued to circulate widely in multiple languages.