June marks the 50th anniversary of the Stonewall riots, which were a catalyzing moment in the struggle for gay and lesbian rights in the United States. The riots, by members of the gay, lesbian, bisexual and transgendered (LGBT) community, sparked in protest to a police raid at the Stonewall Inn in the Greenwich Village neighborhood of New York City.

Police raids often took place at bars frequented by the LGBT community in New York and other cities, such as San Francisco. But on June 28, 1969, a police raid on the Stonewall Inn led to a riot. More protests followed, as advocates for gay rights became more organized.

 At the time of the riots, the LGBT community faced institutionalized oppression in the legal and political systems. For example, it wasn’t until 1973 that the American Psychiatric Association declassified homosexuality as a mental illness.

The Stonewall riots triggered a national movement for LGBT civil rights, one that continues today. Within a few years of the riots, LGBT advocacy organizations had formed nationwide. The first gay-pride marches took place in New York, Chicago, Los Angeles and San Francisco in 1970.

Worldwide pride events will be held this month, including World Pride hosted in New York City, where Pride started with a riot, and marking the 50th anniversary of the Stonewall riots.