Ruth Sulzberger Holmberg, who challenged racial barriers, political skulduggery and environmental adversaries as publisher of The Chattanooga Times in Tennessee for nearly three decades, and who was a member of the family that controls The New York Times, died on Wednesday at her home in Chattanooga. She was 96.

Her family confirmed her death.

Growing up in a newspaper family in New York, Mrs. Holmberg was imbued from adolescence with journalistic traditions of social responsibility, and that heritage became manifest in Chattanooga as she presided over a newspaper known for aggressive, analytical reporting and editorials that denounced racial segregation, exposed government corruption and demanded cleaner air in a city of heavy industry and belching smokestacks.

For years she was a pariah in a city where many regarded her as an Eastern liberal interloper.

Mrs. Holmberg, who was publisher of The Chattanooga Times from 1964 to 1992, stayed on as publisher emeritus and chairwoman until 1999, when it was sold to a small chain and merged with a rival newspaper. (Though it was owned by her family, the paper was never part of The New York Times Company.)

She was a granddaughter of Adolph S. Ochs, who bought The Chattanooga Times in 1878 and The New York Times in 1896, and the second of four children of Iphigene Ochs and Arthur Hays Sulzberger, the publisher of The New York Times from 1935 to 1961.

Her brother, Arthur Ochs Sulzberger, who died in 2012, became publisher of The New York Times and chairman and chief executive of the Times Company. One sister, Marian Sulzberger Heiskell, became a New York civic and philanthropic leader. Another, Judith P. Sulzberger, who died in 2011, became a doctor affiliated with the College of Physicians and Surgeons at Columbia University.

A Smith College graduate who had been a Red Cross volunteer in England and France during World War II, Mrs. Holmberg (her name from a second marriage) was a 25-year-old Sulzberger heiress when she and her first husband, Ben Hale Golden, arrived in Chattanooga in 1946 — not to take over her family’s newspaper but to begin Mr. Golden’s career on it. With no journalistic experience, he was to be groomed for the publisher’s post.

Chattanooga, a city of 140,000 in southeastern Tennessee, was nothing remotely like the New York City where Mrs. Holmberg had grown up, in Manhattan. It did not welcome Eastern liberals or Jews, even secular Jews who, like her, were married to Christians. Racial segregation was practiced there and “outsiders” were distrusted. Music, art and other cultural offerings were limited.

But the couple settled there, and after a long apprenticeship, Mr. Golden was named publisher in 1957. During his seven-year tenure, The Chattanooga Times, a morning paper with a circulation of about 40,000, turned profits but was shunned by many readers and advertisers, who preferred a rival paper that often skirted local controversies and offered a deeply conservative viewpoint.

Mr. Golden resigned in 1964 and was succeeded by his wife. The couple, who had four children, were divorced in 1965. Thrust into the publisher’s suite, Mrs. Holmberg, who had written feature articles and art criticism for the paper but had subordinated herself for years to her husband’s career, took charge decisively. “I was born into the Sulzberger-Ochs family,” she declared, “and am deeply committed to the quality of journalism that these two names have come to exemplify.”

The Chattanooga Times championed the racial integration of schools and universities, supported civil rights legislation in Congress and backed clean-air laws, provoking anger in a city where industrial pollutants shrouded scenic mountain backdrops and whose air, according to a 1969 federal report, was the dirtiest in the nation.

The Times also endorsed reforms to root out corruption in government, expand the voting franchise and give black residents, a third of the population, a larger voice in municipal affairs.

In the 1970s, The Times fought pitched battles with its hometown competitor, The News-Free Press, although the rivalry was muted under a joint operating agreement reached in the 1980s allowing the two papers to operate a single business department but separate newsrooms and editorial voices.

In 1972, she married Albert William Holmberg Jr., who oversaw the production, advertising and circulation departments at the paper. He was later named its president.

As her influence widened, Mrs. Holmberg became nationally prominent. She was elected president of the Southern Newspaper Publishers Association in 1984, and in 1987 became the second woman, after Katharine Graham, the longtime publisher of The Washington Post, to be elected a director of The Associated Press, the dominant news service in the United States.

She and her siblings transferred ownership to their 13 children in 1997. Over the next two years, Walter E. Hussman Jr., head of the Wehco Media Company, bought The News-Free Press and The Times and merged them to become The Chattanooga Times Free Press.

Mrs. Holmberg was on the board of The New York Times for 37 years. Stepping down in 1998, she remained a principal owner of the company under a trust that had passed to her and her three siblings on the death of their mother in 1990.

Ruth Rachel Sulzberger was born in New York City on March 12, 1921. She and her siblings grew up surrounded by maids, butlers, nannies, chauffeurs and other servants. She attended the Lincoln School, an experimental adjunct to Columbia Teachers College; and Brearley, a private school on the Upper East Side, before enrolling at Smith, in Northampton, Mass.

As a college student she wanted to work one day for The Times, and did some reporting on her summer and holiday breaks. She wrote a magazine article about wartime changes at women’s colleges, and once spent two days driving a taxi in New York for a story.

But after graduating in 1943, as World War II raged in Europe, she joined the American Red Cross as an unpaid volunteer and sailed for England. She was assigned to the 394th Bombardment Group of the Ninth Air Force near Chelmsford, 30 miles northeast of London and a few miles from the North Sea coast.

There she lived in a drafty Quonset hut, walked planks over muddy paths and, with her Red Cross comrades, met the B-26 Marauders limping home from missions over the Continent. The airfield was sometimes bombed by German planes, she recalled.

“Whatever they hadn’t dropped on London, they dropped on us,” she told Susan E. Tifft and Alex S. Jones for their 1999 book, “The Trust,” a history of the Ochs and Sulzberger families and The New York Times.

At the military base, she met Ben Golden, a married Army Air Force officer who had been a manager for the Tennessee Valley Authority. After the Normandy invasion in 1944, they moved with the 394th to France and stayed for the duration. Mr. Golden’s first marriage ended in divorce, and within a year after the war, Ruthie, as her father affectionately called her, was married and in Chattanooga, where she would settle, raise her children and make her mark.

Mrs. Holmberg is survived by the four children from her first marriage: Stephen Golden, a retired lawyer who was president of the Times Company’s forest products group; Michael Golden, who recently retired as vice chairman of the Times Company; Lynn G. Dolnick, a Ph.D biologist and retired associate director of the Smithsonian’s National Zoo; and Arthur Sulzberger Golden, author of the best-selling 1997 novel “Memoirs of a Geisha.” Their father died in 1970.

Mrs. Holmberg is also survived by her sister Ms. Heiskell; her stepdaughters, Jeanne Johnson, Meg Duckworth and Elin Holmberg-Rowland; seven grandchildren, eight great-grandchildren, seven step-grandchildren and a number of step-great-grandchildren. Mr. Holmberg died in 2005.

Her nephew Arthur Ochs Sulzberger Jr. is publisher of The New York Times and chairman of the Times Company. One of her grandsons, Sam Dolnick, is an assistant editor of The Times.

Mrs. Holmberg, who received an honorary doctorate in humane letters from the University of Tennessee at Chattanooga in 2007, contributed millions to cultural institutions, universities and educational programs for journalists, notably at the graduate schools of journalism at Columbia University and the City University of New York.

After leaving The Chattanooga Times, she remained active in philanthropy and civic affairs. Among other positions, Mrs. Holmberg was a director of the Smithsonian Institution, a trustee of the University of Tennessee at Chattanooga, a founding member of the Tennessee Arts Commission, a member of the Tennessee Higher Education Commission, chairwoman of the Public Education Foundation, director emeritus of the Hunter Museum of American Art, a director of the Chattanooga Symphony and Opera Association, president of the Chattanooga Area Chamber of Commerce (the first woman to hold that post) and a director of the Chattanooga Community Foundation, the Tennessee Aquarium and the Chattanooga Area Beautification Committee.