Lou Sullivan was born on June 16, 1951, in Milwaukee, Wisconsin. He identified as a trans man from a very early age and moved to San Francisco in 1975 in search of a more accepting environment. While there, he began working at the Wilson Sporting Good Company. He also sought out gender-affirming medical care, but was initially denied treatment because he identified as gay and homosexuality was listed as a contraindication for gender-affirming care at the time by the American Psychiatric Association and World Professional Association for Transgender Health. He campaigned against this and eventually received gender-affirming care in 1979. He wrote frequently about trans identity and experience, publishing The FTM Newsletter, authoring a biography of Jack Garland, and editing The Gateway, the newsletter of Golden Gate Girls/Guys. He was also a founding member of the GLBT Historical Society in San Francisco. Sullivan was diagnosed with HIV after a surgical procedure in 1986 and died of AIDS-related complications on March 2, 1991. He is included on the National LGBTQ Wall of Honor at the Stonewall National Monument and the Rainbow Honor Walk in the San Francisco Castro neighborhood. His journal entries were collected in a book called We Both Laughed in Pleasure. Some of his letters, which address the trans experience in San Francisco, are showcased in Man-i-fest: FTM Mentorship in San Francisco, 1976 -2009, by Megan M. Rohrer.