Henry Havelock Ellis, known as Havelock Ellis (2 February 1859 - 8 July 1939), was a British physician and psychologist, writer, and social reformer who studied human sexuality. He was co-author of the first medical textbook in English on homosexuality in 1897, and also published works on a variety of sexual practices and inclinations, including transgender psychology. He is credited with introducing the notions of narcissism and autoeroticism, later adopted by psychoanalysis. As contemporary progressive thinker, he supported eugenics and served as president of the Galton Institute.
Ellis, son of Edward Peppen Ellis and Susannah Mary Wheatley, was born in Croydon, then a small town south of London. He had four sisters, none of whom married. His father was a sea captain, his mother the daughter of a sea captain, and many other relatives lived on or near the sea. At seven years of age, his father took him on one of his voyages, during which they called at Sydney, Callao and Antwerp. After his return, Ellis attended the French and German College near Wimbledon, and afterward attended a school in Mitcham.
In April 1875, Ellis sailed on his father's ship for Australia; soon after his arrival in Sydney, he obtained a position as a master at a private school. After the discovery of his lack of training, he became a tutor for a family living a few miles from Carcoar. He spent a year there, doing a lot of reading, and then obtained a position as a master at a grammar school in Grafton. The headmaster had died and Ellis carried on the school for that year, but was too young and inexperienced to do so successfully.