OutHistory.org is a public website about lesbian, gay, bisexual, transgender, queer, and heterosexual history, with a non-exclusive focus on the US and Canada.

OutHistory.org was founded in 2004 by Jonathan Ned Katz, author of author of Gay American History: Lesbians and Gay Men in the U.S.A. (1976), Gay/Lesbian Almanac: A New Documentary (1983), The Invention of Heterosexuality (1995), Love Stories: Sex Between Men Before Heterosexuality (2001), The Daring Life and Dangerous Times of Eve Adams (2021), and other works on the history of sexuality and gender.

OutHistory.org has collaborated with other LGBTQ history sites, archives, newspapers, magazines, museum projects, and art galleries, as well as interested researchers.

[9] In May 2016, OutHistory celebrated the 40th anniversary of Gay American History with a conference co-chaired by Claire Potter and Daniel Marshall, Senior Lecturer in Writing and Literature, Deakin University, Melbourne, Australia, and managed by Kevin Ewing.

The 2016 conference, co-sponsored by Arcus, CLAGS, and The New School, brought together hundreds of LGBTQ historians and activists to celebrate the state of our field and learn from one another.

In 2023, OutHistory launched a Fellowship Program which supports the creation of digital exhibitions by fellows, who receive modest stipends for this work.