Iwan Bloch (8 April 1872 – 21 November 1922), also known as Ivan Bloch, was a German dermatologist, and psychiatrist, psychoanalyst born in Delmenhorst, Grand Ducal Oldenburg, Germany, and often called the first sexologist. Together with Magnus Hirschfeld and Albert Eulenburg, Bloch is known for having proposed the new concept of a science of sexuality (Sexualwissenschaft) or sexology. In 1906 he wrote in German the book Das Sexualleben unserer Zeit in seinen Beziehungen zur modernen Kultur which was translated as The Sexual Life of our Time in its Relations to Modern Civilization, a complete encyclopedia of the sexual sciences in their relation to modern civilization. He is also known for having discovered the Marquis de Sade's manuscript of The 120 Days of Sodom, which had been believed to be lost, and published it under the pseudonym Eugen Dühren in 1904. He had previously published Marquis de Sade: his life and works. In 1899 under the same pseudonym, which he used later for the publishing of more works about Sade and Rétif de la Bretonne.

Early life

Bloch came from a Jewish family. His father Louis Bloch (1846–1892) was a cattle dealer from Bassum who had a total of five children with his wife Rosa Lisette Rosette, née Meyer (1845–1921).

Legacy

According to Sigmund Freud, Bloch's studies were instrumental in the development of the anthropological approach to the theory of sexuality. Before Bloch, homosexuality was analyzed using a pathological approach.

Handbook of Sexology and other works

Iwan Bloch began the publication of his Handbuch der gesamten Sexualwissenschaft in Einzeldarstellungen (Handbook of Sexology in its Entirety Presented in Separate Studies) in 1912. Three volumes appeared until the project was aborted because of Bloch's untimely death at age 50, in 1922. (Band 1, Band 2, Band 3: Louis Marcus, Berlin, 1912–25): He had published earlier: Were published after his death: