One of the founding members of the Daughters of Bilitis and one half of the first same-sex couple to be legally married in San Francisco in 2004, Phyllis Lyon, has passed away. She was 95, and reportedly died of natural causes early Thursday.

Lyon and her wife Del Martin were famously the first couple to be granted a marriage license by then Mayor Gavin Newsom on Valentine's Day 2004, and her life was characterized by a commitment to activism and equal rights for all.

"I'm very sad to learn of the death this morning of Phyllis Lyon," writes legendary LGBTQ activist Cleve Jones. "I met Phyllis and Del in 1972 and it changed my life. Two of the most remarkable people I've ever known."

Lyon began her career as a reporter after earning a degree in journalism from UC Berkeley in 1946. Born in Tulsa, Oklahoma in 1924, she made her way to the Bay Area and met her partner for life, Martin, in 1950. The couple moved to an apartment in the Castro in 1953, and in 1955 joined three other lesbian couples in founding the country's first lesbian civil rights organization, The Daughters of Bilitis, according to the San Francisco Bay Times newspaper.

Per the Bay Times obit:

After moving to a home in Noe Valley, which remained their longtime permanent residence, they began publication of The Ladder in 1956. It was the first nationally distributed lesbian publication in the country, and continued until 1972.

In 1964, Lyon and Martin helped to found the Council on Religion and the Homosexual with Glide Memorial Methodist Church. This was the first group in the U.S. to use the word "homosexual" in its name. Three years later, they became the first lesbian couple to join the National Organization for Women, and subsequently helped to expand that influential organization's policies to include lesbian rights.

The couple in 1972 were among the first members of the Alice B. Toklas Democratic Club. That same year, they authored the groundbreaking book Lesbian Woman, which is considered to be a foundational text of lesbian feminism. This work was followed by Lesbian Love and Liberation, published in 1973.

In 1978, the pair chaired San Franciscans Against Proposition 6 (Briggs Initiative). With Cleve Jones and numerous other LGBTQ community leaders, they also became founding contributors of the San Francisco Bay Times. The following year, activists founded Lyon-Martin Health Services and named it after them. Now a program of HealthRight 360, Lyon-Martin Health Services continues to provide specialized, non-judgmental healthcare to women and to LGBTQ individuals.

Del Martin, a San Francisco native who also became a member of Old Lesbians Organizing for Change, passed away in 2008 at age 87. This was not long after the CA Supreme Court made one of several reversals on Prop 8, marriages resumed at SF City Hall, and Newsom reaffirmed Martin's and Lyon's vows.

The pair were featured in numerous documentaries, including 1993's Last Call at Maud's, and 2003's No Secret Anymore: The Times Of Del Martin & Phyllis Lyon.

In the years since, Lyon continued to be active in the San Francisco LGBTQ community, and as the Bay Times reports, she was delighted last fall when SF Playhouse premiered The Daughters, a play based on hers and others' early activism in SF.

Friend Kate Kendall celebrated Lyon's 95th birthday with her in November, and tells the Bay Times that her family wishes to thank all of Lyon's devoted caregivers in her final years.

Lyon is survived by her sister Patricia Lyon, daughter Kendra Mon, son-in-law Eugene Lane, granddaughter Lorri Mon, grandson Kevin Mon, his wife Ellen, and great-granddaughter Kexin Mon.

Still of Lyon (left) and Martin from Last Call at Maud's