Leonore Annenberg, U.S. chief of protocol under President Reagan, widow of former publisher and U.S. Ambassador to Britain Walter H. Annenberg, and steward of the couple's massive philanthropy, died today at Eisenhower Medical Center in Rancho Mirage, Calif.

She had been in declining health, making fewer appearances at the charitable events that were a constant in her civic life. Mrs. Annenberg was 91.

Mrs. Annenberg, who became an equal partner in the family's charitable legacy over the course of her long marriage, assumed control of the Annenberg Foundation in Radnor upon the death of her husband in October 2002. Since its creation in 1989, the foundation has given away $4.2 billion to cultural, educational and medical institutions. Her estimated worth was valued at $1.7 billion, according to Forbes magazine.

In 2007, Mrs. Annenberg accepted the Philadelphia Award, the city's highest civic honor, in a ceremony at the Academy of Music, making the Annenbergs the first regional couple so honored in separate years. Her husband received the award in 1993.

"The University of Pennsylvania would not be what it is today if not for the generosity of Walter and Lee Annenberg," said Kathleen Hall Jamieson, her posts as director of Penn's Annenberg Public Policy Center and former dean of the Annenberg School for Communication at Penn reflective of those gifts. The couple also bestowed schools at the University of Southern California and Brown.

"As my father Walter H. Annenberg would have wished, the Annenberg Foundation will carry our family's commitment to philanthropy into the future," said Mrs. Annenberg's stepdaughter Wallis. "We honor both Ambassador and Mrs. Annenberg by ensuring the foundation's health and vitality to serve the community for generations to come."

As recently as last month, despite declining health, Mrs. Annenberg met with Supreme Court Justices Anthony Kennedy, Stephen Breyer and former Justice Sandra Day O'Connor, a close friend, to discuss teaching the U.S. Constitution to school children, one of myriad Annenberg-funded programs in civic engagement.

Under Mrs. Annenberg's leadership, the Annenberg Foundation, made regional grants to the Art Museum, the National Constitution Center, and the University of Pennsylvania.

The foundation pledged $10 million to keep Thomas Eakins' masterwork The Gross Clinic in Philadelphia, and committed $30 million to relocate the Barnes Foundation to the Benjamin Franklin Parkway.

The Annenbergs' largesse, in the form of substantial gifts to scores of charitable institutions here and across the country, made them the region's most renowned and consistent benefactors for half a century.

The couple's names are affixed to institutions in the United States and Britain, where Walter Annenberg served as ambassador under President Nixon from 1969 to 1974 and Mrs. Annenberg oversaw the restoration of Winfield House, the ambassadorial residence in London, subsidized with $1 million of their own funds.

CHARITY WORK

During her lifetime, Mrs. Annenberg sat on the boards of the nation's most prestigious philanthropies devoted to the arts and education, and received honorary degrees from the Penn, La Salle University and Brown University.

Mrs. Annenberg was the rare individual to be an active trustee of arguably the city's three most prestigious charitable boards - the Philadelphia Museum of Art, the Philadelphia Orchestra and Penn - and consistently among the largest donors to those institutions. The Annenberg name is everywhere on the Penn campus, rivaled only by that of the school's founder, Benjamin Franklin.

"She really cared very deeply about the history and the culture of the city," said the late Philadelphia Museum of Art director Anne d'Harnoncourt in 2006. "There really wasn't another couple like them. We owe them a great deal."

Mrs. Annenberg was a close friend of former Secretary of State Colin Powell - who called her "Mom" - of former British Prime Minister Margaret Thatcher, and of Ronald and Nancy Reagan, who celebrated New Year's Eve at Sunnylands with the Annenbergs and Frank and Barbara Sinatra.

The Annenbergs' 25,000-square-foot Palm Springs-area residence, decorated with Impressionist paintings and Fabergé eggs, boasts a living room the size of a grand hotel lobby. Situated on 650 manicured acres that included a private golf course, Sunnylands was not so much an estate as a principality in the desert.

"She never took herself too seriously," said her friend retired federal Judge Arlin M. Adams. "She was always more concerned about people who had less than her."

Mrs. Annenberg was known for "small acts of unexpected kindness. She was genuinely a nice person," Jamieson said, forever penning notes on her trademark yellow stationary. "She was so gracious and attentive to the things that interested her. Being with the Annenbergs was a special experience. The attention to detail and graciousness beyond what was ordinarily done."

"She was a funny and lively conversationalist, and it was the conversation you remember about being at their home," d'Harnoncourt once recalled. "She understood the art of being a great hostess." D'Harnoncourt called Inwood - their long-time, 13-acre Wynnewood home, which Mrs. Annenberg sold to Eagles owner Jeffrey Lurie in 2007- "not fancy but beautiful."

Walter and Leonore Annenberg were viewed as a strong partnership, rarely apart, with her grace, charm and attention to detail leavening her husband's occasionally less polished ways.

The Annenbergs shared a lifetime interest in Republican politics, the arts and education, the latter becoming a mandate of the foundation under her leadership. With social issues, she was not conservative, and gave generously to abortion-rights organizations and those that supported gays.

Mrs. Annenberg, known as "Lee" to intimates, was credited with influencing her husband's interest in art, especially French Impressionism and Post-Impressionism, and helping to amass an exquisite collection of paintings that was sought aggressively by several major museums, all with strong charitable ties to the couple.

The Annenbergs lived on a scale rarely matched in contemporary American life, dining with royalty and dignitaries, purchasing Cézannes, maintaining a full-time staff of 30 at the Southern California residence.

Mrs. Annenberg was a constant on the charity circuit, chairing myriad social events, lending her name as "honorary chairwoman" to others.

She was one of those elegant women who fixed her style at an early age and rarely wavered in appearance - powdered porcelain skin seemingly untouched by sun, a meringue of blonde hair impervious to the elements, and understated designer suits adorned with exquisite jewelry. She was never one to dress down.

Her name appeared hundreds of times in this newspaper, which the Annenberg family owned from 1936 to 1969, listed weekly in society pages at various charitable events, her designer clothes invariably described. The articles occasionally included a quote or two about an event, but she preferred that her husband do the talking and her actions speak for her.

She was comfortable letting her husband be the more vocal partner. "He chose the public; she chose him," Jamieson said.

The Annenberg fortune derived in part from The Inquirer and the Philadelphia Daily News, owned first by Annenberg's father, Moses, and sold to Knight Newspapers in 1969. Annenberg's company, Triangle Publications Inc., also published the Daily Racing Form, TV Guide, Good Food and Seventeen. Rupert Murdoch purchased Triangle for $3 billion in 1988.

Since her husband's death, Mrs. Annenberg had served as chairman and sole director of the Annenberg Foundation, a task that was said to be initially daunting but which she wholly embraced.

Brian Tierney, chief executive officer of the company that owns the Inquirer and the Daily News, praised Mrs. Annenberg as "an elegant woman who served her country as a dedicated public servant, and was a generous philanthropist to many Philadelphia charities."

"I was so pleased when she accepted our invitation to visit the newspaper in 2006," he said. "She had not visited our building since 1969 and she took a keen interest in our new ownership group."

MANY OFFICES

Mrs. Annenberg was never known as merely a socialite, but as a charitable arbiter. She was the past president and an honorary trustee of the Palm Springs Desert Museum, an honorary trustee of the Performing Arts Council of the Los Angeles Music Center, a member of the Committee for the Preservation of the White House, a former member of the board of the Pennsylvania Academy of the Fine Arts, a charter member of the board of overseers of the Annenberg Institute for School Reform at Brown, and a founding member of the governing boards of the Annenberg Schools for Communication at Penn and the University of Southern California.

"She had a very high sense of her responsibility to the community," Adams said. "I think anyone who has as many material things as she did and to be interested in so many things is very unusual, and to be so relatively humble about it."

Walter Annenberg was her third husband, she was his second wife, and, by all accounts, it was the love match of their lives.

"She was utterly devoted to Walter," d'Harnoncourt recalled a few years ago.

When she resigned as U.S. chief of protocol in January 1982, after only 10 months in the $50,000-a-year post ("the first paying job I ever had," she said at the time, and the last), she explained her decision as an act of love - although her brief tenure had not been without criticism for lavish entertaining, which the Annenbergs subsidized, and for curtsying before Prince Charles upon his arrival in the United States.

"After 30 years of close, harmonious and happy marriage, my priorities are my husband first," she said at the time of her resignation.

"He was very honest about it. He said, 'Honey, I don't know how many years I have left to spend in the desert, and I love you, and I want you with me.' That's all I had to hear."

Through charm, a mastery of the art of hostessing and a thick and ever-open checkbook, Mrs. Annenberg is credited with helping elevate the Annenberg family's stature, bending a then-arthritic Philadelphia social order that excluded most Jewish leaders.

Her graciousness also helped perfume a family legacy tainted by the rough-and-tumble tactics of her husband, whose personal likes and dislikes shaped Inquirer news coverage, and his tough father, Moses, owner of a horse-racing wire service. Moses Annenberg was sent to federal prison for three years for tax evasion and died a month after his release. Walter Annenberg also was indicted in the case, but the indictment was dropped after Moses Annenberg pleaded guilty.

Walter Annenberg's oft-repeated motto, which he kept on his desk at Sunnylands, was "Cause my works on Earth to reflect honor on my father's memory," a crusade Mrs. Annenberg joined him in fulfilling.

Her childhood was comfortable, eventually privileged but not easy.

Leonore Cohn was born Feb. 20, 1918, in New York City, the granddaughter of Russian and German immigrants, and daughter of Maxwell Cohn, the less successful brother of Harry and Jack Cohn, founders of Columbia Pictures.

When she was 7, her mother died in an automobile accident. She and a younger sister were sent to Los Angeles to live with her Aunt Ruth and Uncle Harry, who raised them. She was not spoiled by attention.

Harry Cohn "really was too busy to have a direct influence on me," she said years later, "but I think he always felt that I had ability and that I could do what I wanted to do. I think he wanted me to be something or somebody."

Her daughter Diane Deshong once said of her mother's upbringing, "She never talks much about those early years, but I know that growing up wasn't easy for her. I think how mother grew up without parents and how trying circumstances must have been. There wasn't that loving relationship with a mother, and I think she's tried to make up for it with her own daughters."

Leonore Cohn went to Stanford University, where she studied history and political science, which were to remain lifelong interests, and completed her degree, unlike Walter Annenberg, who attended Penn but did not graduate.

A brief marriage to Belden Katleman, scion of a Southern California family with interests in parking lots and real estate, produced a daughter, Diane.

In 1946, Leonore Cohn Katleman, then 28, married Lewis Rosenstiel, 55, multimillionaire founder of Schenley Industries, the distiller, and had a second daughter, Elizabeth. Rosenstiel was a tempestuous and controversial character, and the marriage was rocky.

'MR. RIGHT'

Four years later, Leonore Rosenstiel met the divorced Walter Annenberg at a party in Boca Raton, Fla., hosted by Henry Crown, the Chicago financier. Lewis Rosenstiel was not in attendance. It was a profound, immediate and mutual attraction.

"He was Mr. Right," Mrs. Annenberg said to the Washington Post in one of the rare interviews she granted. "We thought alike, had the same goals, aspirations and feelings, and we loved to do the same things." She secured a divorce in Reno, Nev., and they were married in 1951.

"A fabulous husband," Mrs. Annenberg said of her spouse of a half-century, "and the thing I love most about him is he's a wonderful companion. We do everything together, and I think that fulfills something I wanted in life and he wanted in life. You know how some men go off and play golf with their men friends? Well, Walter prefers to play golf with me."

Mrs. Annenberg is survived by her sister, Judith Wolf; her daughters, Elizabeth Rosentiel Kabler of New York, amd Diane Katleman Deshong of Beverley Hills; a stepdaughter, Wallis Annenberg; seven grandchildren and seven great-grandchildren.

Plans for a memorial service are pending.

Contact staff writer Karen Heller at 215-854-2586 or kheller@phillynews.com.