Ada Deer, a member of the Menominee tribe in Wisconsin who was a leading figure in the movement for greater Native American sovereignty since the 1960s, a role she played both as a critic of the federal government and as a top official within it, died on Tuesday in Fitchburg, Wis., a suburb of Madison. She was 88.

Ben Wikler, her godson and the chairman of the Democratic Party of Wisconsin, confirmed her death, in a hospital. She had been in hospice care since July.

Ms. Deer racked up a long list of firsts over the course of her life. She was the first member of her tribe to graduate from the University of Wisconsin-Madison and the first to receive a graduate degree; she was also the first woman to lead the Menominee and the first woman to lead the federal Bureau of Indian Affairs.

She came to prominence in the early 1970s, when she moved to Washington, D.C., to help steer the effort to overturn the federal government’s policy of “termination” — a series of laws that since the late 1940s had restricted and in some cases eliminated tribal sovereignty in favor of integration within the rest of American society.

The Menominee lost their sovereignty in 1961, a move that cut off their lifeline of federal financial support.

“Termination was a disaster — politically, economically, culturally,” Ms. Deer said in a 1976 speech. “We were no longer a federally recognized tribe.”

She spent years meeting with representatives and senators, writing briefs and organizing protests. Her work paid off: In 1973, President Richard M. Nixon signed the Menominee Restoration Act, and in 1975, the tribe regained its sovereignty. Ms. Deer became its first chairwoman.

Her lobbying was only a pause from her career as a social worker, and she later taught at the University of Wisconsin’s School of Social Work. She also brought her profession’s commitment to grass-roots action and social justice into her politics.

“She embraced the fact that progress can only come when people pour their hearts and souls into making it happen,” Mr. Wikler said.

Ms. Deer ran for office several times, though never successfully. She ran twice for Wisconsin secretary of state and once for Congress, in 1992, losing a high-profile race against a Republican incumbent, Scott Klug, that nevertheless brought her yet another distinction: as the first Native American woman to win a Democratic primary for federal office.

Her campaign got her the attention of the incoming Clinton administration, which, despite her outspoken criticism of Washington, named her assistant secretary of the interior for Indian affairs in 1993, putting her in charge of the Bureau of Indian Affairs.

On her first day, she insisted that the big desk and small rectangular table in her office be replaced with a small desk and a large round table, to break down the hierarchy that she felt pervaded the bureau. By the next day, her new furniture was in place.

But she wasn’t; almost immediately she set off to tour reservations, her first being Pine Ridge, in South Dakota, among the country’s poorest. She vowed to reform the bureau from top to bottom and make it work for Native Americans.

Inevitably, Ms. Deer found herself facing an insurmountable challenge: The administration expected her to be a team player, while Native Americans expected her to be their advocate.

By the end of her tenure, in 1996, she had made enemies on both sides, though most observers decided that she had done the best with an awful hand. If nothing else, she had successfully defended the agency against severe budget cuts demanded by Republicans in their Contract for America after they took control of Congress in 1994, denouncing them as “genocide.”

Ada Elizabeth Deer was born on Aug. 7, 1935, in Keshena, a town on the Menominee Reservation in northern Wisconsin. Her family was poor, living in a log cabin with no running water or electricity. Her father, Joe Deer, was Menominee Indian and worked in a lumber mill. Her mother, Constance Stockton (Wood) Deer, was a nurse with the Bureau of Indian Affairs in Wisconsin.

Though Constance Deer was white, she believed strongly in Native rights, and from early on she instilled the same belief in Ada. She took her daughter to her first tribal council meeting when she was just 4. She also worked hard to broaden her daughter’s horizons, filling her days with books, pen pals, Girls State programs and riding school.

She even signed her up for a contest, run by Columbia Pictures, to find the “six most beautiful Indian girls in America.” Ada won, and as a prize got to make a cameo appearance in the 1954 western “The Battle of Rogue River.”

Ms. Deer graduated from the University of Wisconsin with a bachelor’s degree in social work in 1957 and received her master’s degree in the same subject from Columbia University in 1961.

She worked briefly in New York City, then moved to Minneapolis to work with Native Americans who were moving to the city in search of opportunities, but who often found the transition to urban life disorienting.

Ms. Deer never married, saying that she thought a family life would slow her down. She is survived by her sisters, Connie Deer and Ferial Deer Skye.

Ms. Deer spent two years in Puerto Rico with the Peace Corps, then returned to Minneapolis to work for the Bureau of Indian Affairs for three years. She left in 1967, frustrated, she later said, by red tape and broken promises.

She served as chairwoman of the Menominee tribe until 1976, after which she became a lecturer in American Indian studies at the University of Wisconsin. She ran the program from 2000 until her retirement in 2007.

Though she never again ran for office after her 1992 loss, Ms. Deer remained involved in politics, especially at the local level around Madison. Among other things, she would volunteer to go door to door with first-time candidates, to help them get over their nervousness in talking with strangers.

On Aug. 7, a week before her death, Gov. Tony Evers declared the date Ada Deer Day in Wisconsin.