La Cage Aux Folles was the first gay musical on Broadway or in the West End, beginning its New York run in 1983. It won Best Musical at that year’s Tony Awards, and ran for four years. Its lyrics and music were written by Jerry Herman, openly gay composer of Mame and Hello, Dolly!, and its book was written by Harvey Fierstein, who performs I Am What I Am, the show’s most famous number, in the video linked.
La Cage Aux Folles is based on the 1973 French film of the same name, though anglophone audiences will know the American remake, The Birdcage, starring Robin Williams, better. It’s a wonderful, joyous farce, much of which takes place in drag, celebrating queer families.
The show flopped in the West End in 1986, despite its Broadway success, something which is normally attributed to the AIDS crisis - AIDS was not well known in 1983, when La Cage opened on Broadway, but by 1986 the unfettered, happy depiction of queer families met with increased homophobia. In later interviews, Herman admitted that the AIDS crisis affected the musical in another way, which was that much of the cast was ill as well. Herman himself contracted HIV in this period, but incredibly survived until only a couple of years ago, when he passed away at 89.
Since then, La Cage has been revived multiple times, including a particularly wonderful 2005 cast starring Kelsey Grammar that I’m listening to right now, and received boatloads of awards. La Cage doesn’t deal with the heavy side of homophobia, preferring to combat prejudice with comedy and farce - what is easy to miss is that, in the 1980s, that happiness was radical and was part of what made the show so controversial. Long live La Cage Aux Folles!