[T]he military is the main reason so many gay men settled in San Francisco. During World War II, the United States armed forces "sought out and dishonorably discharged" homosexuals. Many men who were expelled for being gay were processed at San Francisco bases. . . . Gay men often stayed in the city after completing their military service. . . . Today, San Francisco has the highest concentration of gay men, women, and same-sex couples in the country and possibly the world.
Hat Tip to Defense Tech.