Joseph Henry Gainer (January 18, 1878 – December 15, 1945)[1] was an American politician who served as the 26th mayor of Providence, Rhode Island.

His parents, John and Margaret (Keogh), were born in Ireland and settled in Providence's North End, where they operated a grocery store.

[2][3][4] He went on to earn a law degree from the Catholic University of America in 1902,[2] and passed the Rhode Island bar examination the same year.

[2] At age 34, Gainer was the youngest person elected mayor in Providence history at the time.

Although Gainer carried Providence, his popularity was not enough to win the state; he lost the election by over 16,000 votes.

[2] After losing this election, Gainer returned to his law practice,[2] having served a total of seven terms of office.