Harold Leland "Hal" Call was an American businessperson, LGBT rights activist, and U.S. Army veteran. He served as president of the Mattachine Society and in the 1950s, was one of the first gay activists to speak publicly on television. Call founded printing presses for LGBT publications and later opened gay adult shops and pornographic film screening venues. He received a Purple Heart for his service in the Pacific War.

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.