DURHAM — Mary Duke Biddle Trent Semans, a descendant of the Duke family who was devoted to philanthropy, education, human rights and the arts, died Wednesday after a short period of declining health. She was 91.

Semans was born into extraordinary privilege as a member of the family that founded Duke University. She was great-granddaughter to Washington Duke, granddaughter of Benjamin N. Duke and Sarah Duke, and daughter of Mary Duke and Anthony Biddle. Yet she didn't get caught up in a whirlwind of ball gowns and blue bloods. She once said, "New York society terrified me. ... I'm not good at keeping up with the Joneses."

Instead, she set about living a life of substance in Durham, where she married twice, raised seven children and served in a seemingly endless number of roles, including mayor pro tem of Durham in the 1950s, trustee at Duke University and trustee of several family foundations, including the Charlotte-based Duke Endowment and The Mary Duke Biddle Foundation, named for her mother.

Duke University President Richard Brodhead sent an email message to the Duke community Wednesday, saying that Semans "supported every good thing that has happened at this university." But she was more than the sum of her accomplishments, he said.

"She had a care for others and a belief in human possibility that made every encounter an inspiring event," Brodhead's email said. "All who experienced her grace, warmth, enthusiasm and can-do spirit will remember her for years to come. Duke mourns the passing of one of its greatest friends."

Semans was always there, at every Founder's Day convocation, every Duke celebration. She was a close confidante of Terry Sanford, the former Duke president and North Carolina governor. She was a big fan of men's basketball Coach Mike Krzyzewski, too.

"She was the conscience of the university," said Dr. Keith Brodie, former Duke president. "She was the go-to person when someone was going through a tough time. She wielded great power in her sweet, diminutive way."

Devotion to Durham

As devoted as she was to Duke, Semans was similarly committed to her adopted hometown of Durham, where she was a beloved figure across socioeconomic lines.

She was a passionate supporter of civil rights, working for affordable housing in Durham and serving for nearly three decades on the board of Lincoln Community Health Center, a provider of health care to low-income residents.

"Mrs. Semans was the heart of Durham," said Durham Mayor Bill Bell. "Mary just touched all races and all levels of income. She seemed to do it comfortably."

In 1987, Semans told Duke Magazine why she felt compelled to reach out to people: "My feeling is that we are all here for each other. I take very seriously this business of treating your neighbor as yourself, trying to be your brother's keeper. They're solid maxims for life."

She passed her advice to Duke graduates during a 1983 commencement speech. "I am pleading for an extraordinary devotion to humanity. In addition to your employment, do something that benefits the human condition."

Semans lived out that credo, taking on issues such as poverty and racial discrimination with intense intellect and fierce determination. She read several newspapers daily and was an astute observer of politics.

But she never took herself too seriously. A petite dynamo, she had a big mane of light brown curls and was known to wear mini skirts well into her golden years.

Tooling around Durham, Semans offered hugs to acquaintances in the grocery store or at the Guglhupf Bakery near her Forest Hills home. She would meet people, and a year later, remember their names and their children's names. A prolific correspondent, she mailed handwritten notes of thanks for the smallest gesture or congratulations on an accomplishment.

Doug Zinn, executive director of The Mary Duke Biddle Foundation, said Semans was the definition of charm.

"She was the embodiment of goodness," he said. "If people met her just once, they felt like they knew her for a lifetime. She loved people, and she was beloved."

Arts lover

The influence of Semans and her late husband, Dr. Jim Semans, extended beyond Duke and Durham.

They were patrons of the arts in North Carolina, where they were instrumental in the early days of the N.C. School of the Arts, now UNC School of the Arts. They were the largest contributors to the school's former International Music Program and traveled with the students for more than 30 years on European tours, where Semans spoke French and Italian.

They gave to an international dance program at the school and established an endowment fund for the school's library, which is named for them. They donated to scholarship funds and grant programs for students to do special creative projects. The couple, whose Durham home was filled with art, relished their role at the school and nurturing young artist careers. They could be found in the front row of school performances, leading the standing ovation.

The public arts school in Winston-Salem was in mourning Wednesday.

"Mary Semans was the mother of UNCSA, and like the great mother she was, her love for the school was unconditional," said UNCSA Chancellor John Mauceri. "That she led, supported and inspired this school from the moment it was imagined to the cusp of its 50th birthday was in and of itself miraculous. It is hard to imagine going forward without her. ... If there was one word to describe Mary Semans it would be 'beautiful' in every sense of that word."

The Semanses also were big supporters of the N.C. Museum of Art in Raleigh. In 1966 at the state museum, her family foundation established the Mary Duke Biddle Gallery for the Blind, among the world's first sculpture collections meant to be experienced through touch.

Life as a Duke

Mary Duke Biddle was born in New York City on Feb. 21, 1920. Her father, a U.S. Army general, later became a diplomat and was U.S. Ambassador to Poland when Hitler invaded the country in 1939. Later, he served as ambassador to Spain.

She was raised in Manhattan, where her early education included trips to great museums, theater and listening to radio news with her father. But her parents separated when she was in her teens, and her mother returned to Durham with the children. They lived for a time with her grandmother, Sarah Duke, who was devoted to the university and to the state. "We were brought up to think the governor of North Carolina was someone sacred," Semans said in a 1969 interview.

At 15, she enrolled at Duke to study history. She graduated in 1939 and married Dr. Josiah Trent, who would become a professor of surgery at Duke. The couple had four daughters, but Trent died of lymphoma in 1948. A young widow with four children, Mary Trent carried on. She ran for Durham City Council and won.

A few years later, she married Semans, another Duke surgeon and professor of urology. They had three children together and were married more than 50 years until Semans' death in 2005.

Throughout her life, Semans received dozens of awards, honorary degrees and tributes. The atrium at Duke's Nasher Museum of Art is named the Mary D.B.T. Semans Great Hall. And a100-year-old fountain was restored in her honor and moved to the center of the rose garden at the Sarah P. Duke Gardens, a place named for her grandmother.

Semans is survived by her seven children: Mary Trent Jones of Abingdon, Va.; Sarah Trent Harris of Charlotte; Dr. Rebecca Trent Kirkland of Houston; Barbara Trent Kimbrell of Sullivan's Island, S.C.; Jenny Semans Koortbojian of Durham; James Duke Biddle Trent Semans of Chapel Hill; and Beth Semans Hubbard of Los Angeles; 16 grandchildren and 29 great-grandchildren.

A funeral service is planned for Monday at 2 p.m. at Duke Chapel. Funeral arrangements are being handled by Howerton-Bryan Funeral Home.

News researcher Brooke Cain contributed.

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