Several organizations joined together in 1994 and declared October as National Lesbian, Gay, and Bisexual History Month (LGBHM). The celebration is modeled after and is similar in purpose to Black History Month and Women's History Month. LGBHM is designed to "promote the teaching of LesBiGay history in secondary and post-secondary academic setting, as well as within the LesBiGay community and mainstream society" (Lesbian and Gay History Month press release, June 24, 1994). The theme for 1998 is "Find the Facts, Know the Truth".
October was selected because the first and second Marches on Washington for lesbian and gay rights were held in this month in 1979 and 1987. National Coming Out Day (October 11) provided an additional reason for choosing this month. Finally, since October also falls during the academic calendar year, educational institutions are able to participate in LGBHM related activities.
The Gerber/Hart Library & Archives provides additional information about LGBHM.