Marcuse was an intellectual at the Institute for Social Research (known as the Frankfurt School).

• Known as "the Father of the New Left", he criticized what he viewed as new forms of social control, such as the authoritarianism of the Soviet Union.

He wrote Eros and Civilization (1955), a book that played a major role in the development of LGBT subcultures and liberation movements in the 1960s.

• He worked for the Office of Strategic Services (OSS)–the precursor to the U.S. Central Intelligence Agency (CIA)–from 1943 to 1950.