He corresponded for many years with Dr Mary Walker and attempted to secure her collection of pictures and letters.
He was known to Magnus Hirschfeld when the latter was writing Die Transvestiten.
Later, after emigrating to New York, he headed 'a large business' and was a writer and lecturer.
His biography was the first of a transvestite to be presented in the US, in a paper given by Bernard Talmey to the New York Society of Medical Jurisprudence in December 1913, and published the next year in the New York Medical Journal. Spengler himself quoted this article in a letter to the New York Evening Post in 1933.
He became a regular medical patient of Harry Benjamin in the 1920s, and only in 1938, while treating him for arthritis, did Benjamin realize that he was a transvestite. At Spengler’s request he prescribed estrogenic hormone and x-ray sterilization of the testicles. This was Benjamin’s first transgender case.
Spengler is given the pseudonym Rudolph von H. in George Henry’s book.
*Not the German political philosopher.
- Bernard Simon Talmey. "Transvestism. A contribution to the study of the psychology of sex", New York Medical Journal, 21 Feb 1914, pp.362-368. Incorporated into his Love, a Treatise on the Science of Sex-Attraction: For the Use of Physicians and Students of Medical Jurisprudence. New York: Practitioners' Pub. Co, 1915: 298-307. Partially reprinted in Jonathan Katz. Gay/Lesbian Almanac. Harper & Row. 1983: 344-8.
- Otto Spengler. Letter to the Editor. New York Evening Post, February 15 1933.
- George W. Henry. Sex Variants: A Study of Homosexual Patterns. New York: P.B. Hoeber 1948: 487-98.
- Leah Cahan Schaefer & Connie Christine Wheeler. “Harry Benjamin's first ten cases (1938-1953): a clinical historical note”. Archives of Sexual Behavior 24:1 Feb 1995: 3. Online at www.helen-hill.com/pdf/hbfirst10cases.pdf.
- Joanne Meyerowitz. How Sex Changed: A History of Transsexuality in the United States. Cambridge, Ma, London: Harvard University Press. 363 pp 2002: 46, 298n105.