In May, her family reported that she was living with dementia; last week, they said that she had entered hospice care. The Carter Center said she “died peacefully, with family by her side.” Her husband, who turned 99 last month, has been in hospice care since February.

Carter, who married the future governor and president in 1946, was widely credited with expanding the role of first lady beyond the nation’s most prominent hostess to an active partner in policy and international travel, becoming a trusted adviser even in an era when most newspapers would only call her “Mrs. Carter.”

“Rosalynn Carter set a new precedent for first ladies,” wrote historian E. Stanly Godbold, author of “Jimmy and Rosalynn Carter: A Biography.“ “She established the Office of First Lady, worked side by side with her husband as an equal partner in most of the responsibilities of the presidency, and actively pursued her own agenda to make the world a gentler place.“

The Carters were perceived as exemplars of the “new” South in the 1970s, a marked change from the years of George Wallace, John Patterson, Lester Maddox and other Southern governors who thrived on rage and intolerance in support of segregation and states’ rights — and who, at least some of the time, countenanced extrajudicial violence against African Americans.

Jimmy Carter, as much as it was possible for an ambitious political leader to do so, projected beneficence, not bitterness, and Rosalynn Carter was a picture-book complement to her husband, a woman of gentle grace. It was these traits that made them much-admired figures long after Jimmy Carter’s thorny presidency had left his reputation nowhere to go but up.

In their long post-presidential lives, she would remain by his side through public and private matters.

“The best thing I ever did was marrying Rosalynn. That’s a pinnacle in my life,” Jimmy Carter would say.

Eleanor Rosalynn Smith was born Aug. 18, 1927, in Plains, a small Georgia town that certainly didn’t know it was on its way to becoming world-famous. Her father died of cancer when she was 13, leaving her with extended family responsibilities in difficult financial times.

Her future husband was also from Plains. They first dated when she was 17 — she was a friend of his sister’s — and a student at Georgia Southwestern College, and while he was attending the Naval Academy in Annapolis, Md.

“I thought he was the most handsome young man I had ever seen,“ she would say later. Jimmy Carter would tell his mother after the first date that he had met his future wife.

In her autobiography, Rosalynn Carter said that she didn’t accept his first proposal, determined as she was to honor a promise to her father to finish college. On July 7, 1946, shortly after Jimmy’s graduation, they were married. The couple had four children, the youngest of whom, Amy, would grow up in the public eye in the White House.

The family returned to Plains in 1953, and Jimmy Carter entered politics a few years later. By 1970, she was making speeches for him as he ran for governor of Georgia.

In December 1974, her husband launched his presidential campaign. He started as the longest of longshots, but, amazingly, Carter ended up getting elected in November 1976.

During that underdog campaign, Rosalynn Carter visited more than 40 states on his behalf, maintaining a busy speaking schedule.

“It drew us closer together,“ she told a Plains audience 40 years later. “We were separated for 18 months during the campaign. I always felt like he could not have won without me.”

Her husband then added: “We used the wisdom and advice of each other throughout.”

She established a different tone for a first lady even before he took office: She chose to wear the same gown to the inaugural balls she had worn when Jimmy was sworn in as a governor in 1971.

“It enhanced the incoming Carter presidency’s notions of modesty and frugality,” Smithsonian curator Lisa Kathleen Graddy said years later.

Once they were in the White House, it was clear the first lady would have a meaningful role: She had her own office and sometimes attended Cabinet meetings.

In June 1979, The New York Times described her partnership with her husband in “The Importance of Being Rosalynn.” The article shined a light on their weekly working luncheon, one that the Times said was devoid of typical husband-and-wife small talk.

“For the next 40 minutes, the Carters explore a wide range of subjects as they sit through a meal of lamb chops, baby potatoes and salad. They customarily discuss the minutiae of political appointments and the status of the White House staff; they weigh the future of their pet bills in Congress and the fate of Mrs. Carter’s favorite projects; they consider lobbying efforts and campaign plans. Their discussions move from domestic politics to assessments of China, Iran, and the latest events in the Middle East,” the Times wrote.

The president added: “I have found, that the more that she and I can share responsibilities, with her being in an unofficial position and me in an official position, then that tends to strengthen the personal kind of relationship between husband and wife.”

Her advice sometimes led to important breakthroughs. It was at her suggestion that Jimmy Carter invited Prime Minister Menachem Begin of Israel and President Anwar Sadat of Egypt to Camp David, which became the site of their stunning 1978 peace deal.

She made her presence felt around the globe. In 1977, she embarked on a 13-day trip that took her to Jamaica, Costa Rica, Ecuador, Peru, Brazil, Colombia and Venezuela, drawing praise for her knowledge and empathy. An official in Peru called her “highly competent,” and she was praised in Ecuador as “a lively spokesman of the greatest good will.”

In November 1979, she visited tens of thousands of Cambodian refugees in Thailand. The trip was widely credited with increasing awareness of a humanitarian crisis created by years of war, tyranny and international indifference.

“Rosalynn Carter walked among the hungry and the dying, trailed by 150 reporters,” wrote George Packer of the Thailand-Cambodia trip in 2015. “She held a starving baby in her arms while speaking to the infant’s mother, who lay on the ground. ‘Give me a smile,‘ she told another woman, kissing her forehead. Afterward, Mrs. Carter said that she wanted to hurry home ‘and tell my husband.‘”

Carter had other causes she made her own. She fought for ratification of the Equal Rights Amendment, attempting “to present ERA in a way that would appeal to mothers, housewives and Southerners,” Texas Christian University professor Elizabeth Flowers said. Despite her efforts, time ran out before the ERA amendment was approved by the required number of states.

She was an advocate for mental health, serving as an honorary member of the President’s Commission on Mental Health and lobbying on behalf of the Mental Health Systems Act of 1980. Implementation of that law, however, was left to the incoming Reagan administration, which had little interest in it. “The incoming president put it on the shelf,” she lamented in 2013.

She was also an articulate defender of the United States. In 1978, the Russian writer and dissident Aleksandr Solzhenitsyn assailed America and the West during a speech in Harvard: “Destructive and irresponsible freedom has been granted boundless space. Society appears to have little defense against the abyss of human decadence.“ Addressing the National Press Club, Rosalynn Carter responded: “I’m not a Pollyanna about the mood of the country, but I can tell you flatly — the people of this country are not weak, not cowardly and not spiritually exhausted.”

After Jimmy Carter failed to win reelection in 1980, the couple returned to Plains. In the decades afterward, they were involved in a seemingly never-ending series of public activities, many of them for charity. They could frequently be seen helping to build houses on behalf of Habitat for Humanity. The two also founded the Carter Center, a worldwide organization.

“The Carter Center is guided by the principles of our Founders, Jimmy and Rosalynn Carter,” it said on its website. “Founded, in partnership with Emory University, on a fundamental commitment to human rights and the alleviation of human suffering, the Center seeks to prevent and resolve conflicts, enhance freedom and democracy, and improve health.”

In 2013, she expressed delight when the Obama administration issued a rule designed to expand access to mental health care decades after her efforts to do so. “As soon as I heard it, I started shaking, you know? … I had wanted it, so it was exciting. It was emotional,” Carter said.

During the 2016 presidential season, she made a rare campaign appearance in Albany, Ga., on behalf of Democratic candidate Hillary Clinton. “A thing I like about Hillary is she’s a mother and a grandmother. She has one daughter and two grandbabies, and she’ll be concerned about children,” she said.

In October 2019, the Carters surpassed George H.W. Bush and Barbara Bush as the longest-married presidential couple of all time. (The Bush marriage lasted from January 1945 until her death in April 2018.)

Pundits dug up quotes to try to explain their longevity, even as the two continued to speak at the Carter Center, attend sporting events or attend church in Plains, where he taught Sunday school and then posed for photos afterward with visitors.

“She leaves a legacy,” Godbold said of Rosalynn Carter, “of improved care for the mentally ill, help for the vulnerable in American society, successful peace initiatives in the Middle East and elsewhere, and the advancement of human rights around the globe. A master politician, diplomat, as well as caring mother and wife, she was intimately involved in every aspect of the Carter presidency.”

She is survived by her husband and her four children — Jack, Chip, Jeff and Amy — as well as, according to the Carter Center, 11 grandchildren and 14 great-grandchildren.

“Her life of service and compassion was an example for all Americans,” Chip Carter said in a statement on Sunday.