One of the most significant civil rights cases in recent U.S. history started with a tax bill.

Edith Windsor and Thea Spyer wed in 2007 in Canada after four decades together. When Spyer died two years later, the IRS ordered $363,000 in taxes paid by her estate. The federal government, because of the Defense of Marriage Act, did not recognize their same-sex union.

Windsor appealed. She was the lead plaintiff of a lawsuit alleging unconstitutional discrimination, and in 2013, the Supreme Court struck down DOMA in 13 states and Washington.

“It’s an accident of history that put me here,” Windsor said. “If Thea had been Theo,” everything would have been different, she added, according to Reuters.

“Marriage’ is a magic word,” according to the New Yorker. “Thea looks at her ring every day, and thinks of herself as a member of a special species that can love and couple ‘until death do them part.’”

In 2015, another Supreme Court decision extended protections and privileges for any married couple regardless of their gender across the country.

“This decision affirms what millions of Americans already believe in their hearts: When all Americans are treated as equal, we are all more free,” then-President Barack Obama said following that ruling.

Windsor, 88, died Tuesday from an unspecified illness in New York City, her wife, Judith Kasen-Windsor, said.

She knew personal triumphs carried dramatic changes to the social fabric of the country, and in 2013, with same-sex unions recognized in only part of the country, Windsor foresaw transformation taking place.

“Children born today will grow up in a world without DOMA. And those same children who happen to be gay will be free to love and get married — as Thea and I did — but with the same federal benefits, protections and dignity as everyone else,” Windsor said, according to NBC News. “If I had to survive Thea, what a glorious way to do it — and she would be so pleased.”

Windsor’s death left a wake of former presidents, politicians and activists reflecting on her activism that began in earnest at 81.

Barack Obama

“America’s long journey towards equality has been guided by countless small acts of persistence, and fueled by the stubborn willingness of quiet heroes to speak out for what’s right.

Few were as small in stature as Edie Windsor — and few made as big a difference to America,” Obama said on Facebook.

“I thought about all the millions of quiet heroes across the decades whose countless small acts of courage slowly made an entire country realize that love is love — and who, in the process, made us all more free. They deserve our gratitude. And so does Edie.”

Hillary Clinton

“Edie Windsor showed the world that love can be a powerful force for change. She will be greatly missed.”

Bill Clinton

“In standing up for herself, Edie also stood up for millions of Americans and their rights. May she rest in peace,” Clinton said Tuesday.

Judith Kasen-Windsor

“I lost my beloved spouse Edie, and the world lost a tiny but tough-as-nails fighter for freedom, justice and equality,” Kasen-Windsor, whom Windsor married last year, said. “Edie was the light of my life. She will always be the light for the LGBTQ community which she loved so much and which loved her right back.”

George Takei

“Edith Windsor changed history by winning her case and ushering in marriage equality. Her legacy will live on forever. Rest in peace, Edie,” the actor and gay rights activist tweeted.

Rep. Nancy Pelosi (D-Calif.)

“Today, we mourn the loss of Edie Windsor. With pride & bravery, she refused to accept injustice. Your legacy of LOVE moved us ALL forward,” Pelosi said on Twitter.

Rep. Barbara Lee (D-Calif.)

“Edith Windsor will be remembered as a great American civil rights hero. #ShePersisted & showed the world that #LoveIsLove. Rest in Power,” the congresswoman tweeted.

New York Mayor Bill de Blasio

“The arc of the moral universe bends toward justice. But sometimes it needs a good kick in the ass from people like Edie Windsor,” de Blasio tweeted.

American Civil Liberties Union

“One simply cannot write the history of the gay rights movement without reserving immense credit and gratitude for Edie Windsor,” Anthony Romero, the executive director of the ACLU, told the Associated Press, adding that Windsor was “one of this country’s great civil rights pioneers.”

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