Henry Havelock Ellis was a pioneer of sexology, the scientific study of human sexuality. As he details in his memoir My Life (1939), he grew up in South London, England, and had an open marriage with Edith Ellis (née Lees) (1861–1916), who was a lesbian. Ellis is best known for his seven-volume series, Studies in the Psychology of Sex (1897–1928). The earliest of these volumes, a study of (mostly male) same-sex behaviors entitled Sexual Inversion (inversion being Ellis’s preferred term for ”homosexuality,” a term he disliked) appended writings by poet and sexologist J. A. Symonds (1840–1893). The book was banned in Britain on grounds of obscenity, forcing Ellis to publish all further writings in the United States. Ellis was an early theorist of what he termed ”erotism,” developing influential concepts and theories regarding auto-erotism, sadism, masochism, and fetishism. Ellis participated, with Richard von Krafft-Ebing (1840–1902) and Sigmund Freud (1856–1939), in the burgeoning study of non-normative sexual practices, which he grouped under the umbrella term “erotic symbolism” (Ellis cited in Schaffner: 99). Suggesting that “abnormal” expressions of sexuality were congenital and harmless, Ellis advocated for the reform of laws that criminalized acts of “inversion” (homosexual acts) in public and private. A proponent of eugenics, Ellis also shared a long-standing friendship with American contraceptive-rights leader Margaret Sanger.