William George Hayden was born in Ipswich, Queensland, the son of an Irish-American sailor. He was educated at Brisbane State High School and served in the Queensland Police Force from 1953 to 1961.
He furthered his education through private study, completing an economics degree at the University of Queensland.
As minister for social security between 1972 and 1975 and treasurer in 1975, he introduced much welfare legislation, including the universal health insurance scheme Medibank.
Hayden was the leader of the Australian Labor Party between 1977 and 1983, minister of foreign affairs from 1983 to 1988, and Australian governor-general from 1989 to 1996.
He spoke openly in support of euthanasia and of marriage and adoption rights for homosexuals in 1995.