Harry Hay, English-American activist, co-founded the Mattachine Society and Radical Faeries (born 1912)

Henry Hay Jr. was an American gay rights activist, communist, and labor advocate. He cofounded the Mattachine Society, the first sustained gay rights group in the United States, as well as the Radical Faeries, a loosely affiliated gay spiritual movement. Hay has been described as "the Founder of the Modern Gay Movement" and "the father of gay liberation".

The Mattachine Society, founded in 1950, was an early national gay rights organization in the United States, preceded by several covert and open organizations, such as Chicago's Society for Human Rights. Communist and labor activist Harry Hay formed the group with a collection of male friends in Los Angeles to protect and improve the rights of gay men. Branches formed in other cities, and by 1961 the Society had splintered into regional groups.

Radical Faeries are a loosely affiliated worldwide network and countercultural movement blending queer consciousness and secular spirituality. Sharing various aspects with neopaganism, the movement also adopts elements from anarchism and environmentalism. Rejecting hetero-imitation, the Radical Faerie movement began during the 1970s sexual revolution among gay men in the United States. Gay activists Harry Hay, Mitch Walker, Don Kilhefner, and John Burnside organized the first Spiritual Conference for Radical Faeries in September 1979.