Gilbert Baker, a self-described “gay Betsy Ross” who in 1978 hand-dyed and stitched together eight strips of vibrantly colored fabric into a rainbow flag, instantly creating an enduring international symbol of gay pride, was found dead on Friday at his home in New York City. He was 65.

Cleve Jones, a friend and gay rights activist who confirmed the death, said that Mr. Baker had a stroke several years ago but had not been sick recently.

As the gay rights movement spread from San Francisco and New York in the 1970s, Mr. Baker was often asked by friends aware of his creative talents to make banners for protests and marches. His creations, like others during that time, often included the pink triangle, which protesters had claimed as an icon after its initial use by the Nazis to identify gay men in concentration camps during World War II.

Before a gay pride parade in 1978 in San Francisco, Harvey Milk, a city supervisor and gay rights leader who was assassinated that year, joined others in asking Mr. Baker to create an emblem to represent the movement.