April 9 (UPI) -- LGBTQ activist Phyllis Lyon, known as a pioneer of same-sex marriage in California, died on Thursday at the age of 95.
Calfornia state senator and chair of the legislative LGBTQ caucus, Scott Wiener, announced on Twitter that Lyon died of natural causes.
"We lost a giant today," Wiener wrote. "Phyllis Lyon fought for LGBT equality when it was neither safe nor popular to do so. Phyllis and her wife, Del, played a crucial role in winning the rights and dignity our community now enjoys."
Lyon and her wife, Del Martin, co-founded the first lesbian rights organization in the United States in 1955.
The couple first married in 2004 when Lyon was 80 years old and Martin was 83, after San Francisco allowed same-sex couples to wed, but the union was ultimately voided by the courts.
California Gov. Gavin Newsom, who served as mayor of San Francisco from 2004-2011, officiated a second wedding between the couple in 2008 after the Supreme Court struck down the state's same-sex marriage ban.
"Phyllis and Del were the manifestation of love and devotion. Yet for over 50 years they were denied the right to say 2 extraordinary words: I do," Newsom wrote on Twitter Thursday afternoon. "Phyllis -- it was the honor of a lifetime to marry you and Del. Your courage changed the course of history."
Martin died in August 2008, months after their wedding.