Born as Edward Sagarin to Russian Jewish parents in Schenectady, New York, Cory was born with scoliosis and suffered his entire life from a disfiguring hunchback. He enrolled at the City College of New York, but was forced to drop out of college due to the Great Depression.

In 1934, Sagarin met Gertrude Liphshitz, a woman who shared his left-wing political interests. They married in 1936 and soon after, Gertrude gave birth to a boy. Sagarin established himself in the perfume and cosmetics industry, becoming knowledgeable about the chemistry of perfumes, and publishing The Science and Art of Perfumery in 1945.

Donald Webster Cory's book, The Homosexual in America, was published in 1951, and it became one of the most influential works in the history of the gay rights movement. The first nonfiction, insider account of the gay American subculture by an avowed homosexual, Cory's book politicized numerous gay men and lesbians and earned him the title "father of the homophile movement."