After doling out hundreds of millions of dollars over several decades, one of the few major philanthropies in the Philadelphia region began a quick fade from the scene with the death yesterday of its ardent doyenne of hometown causes.

Leonore Annenberg, the region's voice in decision-making at the Annenberg Foundation, died in the morning in California, and by late in the day officials had confirmed that the Annenberg Foundation would move its headquarters from Radnor to Los Angeles.

Longtime executive director Gail C. Levin is stepping down, and control of the foundation has been transferred to Mrs. Annenberg's stepdaughter, Wallis, and three grandchildren living in Los Angeles and Paris.

"Now it's time for a new generation to take over," Levin said. "They will be doing the work of interest and importance to them."

Asked whether grant-making in Philadelphia would be given any special consideration in the future, Levin said:

"I don't know that there will be any special consideration. Clearly they are deeply interested in their surroundings in Southern California and California at large, and they have been and will be doing work elsewhere."

She said the Radnor office would be kept open to "support the Los Angeles trustees" with accounting and human-resources functions. A foundation spokeswoman in Los Angeles declined to say anything about funding in the Philadelphia area. "We do not know what is going to happen in Philadelphia yet. It is just too soon."

Whatever its future, the multibillion-dollar foundation led by Mrs. Annenberg since the death of husband, Walter, in 2002 has had a stunning run in Philadelphia, supporting projects in media, education, health care, historic preservation, and the arts with hundreds of millions of dollars in gifts.

"It's the end of an era as far as the Annenberg Foundation is concerned, because Lee is gone and the foundation will now be run by Wallis, so they will no longer have any impact in Philadelphia," said H.F. "Gerry" Lenfest, who frequently joined forces with Mrs. Annenberg and the Pew Charitable Trusts on major civic projects. "It will primarily be Los Angeles."

Rebecca W. Rimel, president of the Pew Charitable Trusts, said Mrs. Annenberg's death meant the end of the powerhouse philanthropic trio of Pew, Lenfest, and Annenberg that helped push forward the Barnes Foundation's move to the Parkway and rescued a financially strapped Kimmel Center.

"One important leg of that stool is not available to us any longer," Rimel said yesterday.

Still, she said, Mrs. Annenberg had ensured that funding for the Barnes move would be locked in: "She was a superb businesswoman."

(In addition to Lenfest and the Pew, the best-funded Philadelphia-focused philanthropy is the William Penn Foundation, supported by the Haas Family Trusts.)

More than a year ago, the Annenberg Foundation - with assets of $2.7 billion as of 2007 - began to telegraph on its Web site that a transition was in process, featuring biographies of Wallis and the Annenberg grandchildren in Los Angeles and Paris and describing their involvements in projects internationally.

After her husband's death, Mrs. Annenberg, with longtime residences in Wynnewood and California, took control of the foundation, but from the beginning she had played an equal role in deciding how and where to spread their wealth.

"I don't think anybody has been more generous to Philadelphia than Lee Annenberg and the Annenberg Foundation," Lenfest said, "to the Philadelphia Museum of Art, the Kimmel, Lankenau, Jefferson Hospital. In Philadelphia there's hardly any major organization in the city that she didn't benefit."

One of her last passions is still taking form at the Academy of Music, where she was lead funder for an $8.5 million renovation of the ballroom. It is expected to reopen in July.

That project, for which she gave $5.3 million, was just the tip of the iceberg on the Avenue of the Arts. She gave $15 million to the Academy's endowment, $50 million to the orchestra's endowment, and tens of millions more to the renovation of the Academy.

At one point, Walter Annenberg offered to pick up the entire $40 million tab for restoring the old hall. The gesture shook loose tens of millions in donations from others.

The orchestra will dedicate this weekend's concerts to Mrs. Annenberg.

The largesse sometimes took nonmonetary forms.

Two important Cézanne sketchbooks went to the Philadelphia Museum of Art in 1987 - "wonderful things for a museum to have in terms of showing how an artist works," said Alice Beamesderfer, the museum's interim head of curatorial affairs. "They put the rest of the Cézanne collection in a new light because you can see some of the ideas behind the painting."

The sketchbooks are two of dozens of works the couple gave to the Art Museum. Late in life, Mrs. Annenberg even gave the museum the dresses off her back: an Oscar de la Renta, a Bill Blass, and other sartorial gems now part of the museum's costumes collection.

The museum, however, did not get the Annenbergs' choice collection of Impressionist and Postimpressionist paintings, drawings, and watercolors. That breathtaking cache went to the Metropolitan Museum of Art.

Mrs. Annenberg filled the modest role of civic savior, coming to the rescue (with others) of Thomas Eakins' The Gross Clinic when it was on the verge of leaving the city in 2006.

Education was a major interest for both Annenbergs. A gift of $100 million went to the Peddie School in Hightstown, N.J. And their impact on the University of Pennsylvania has been, to use institutional jargon reserved for the highest expressions of generosity, "transformational."

Over the last 50-plus years, the two have given nearly $500 million to Penn for its Annenberg School for Communication, its policy center and a variety of other initiatives, university officials estimate.

The giving began in 1958 when the couple founded the communications school at Penn.

They funded the program through five-year contracts until 1993, when they made the breathtaking $120 million endowment donation, which still is the largest gift in Penn's history. That gift provided permanent funding for the communications school and created the Annenberg Public Policy Center, the only major policy center focused on communications in the country.

In 2002, Mrs. Annenberg made an additional $100 million gift to the school and center to protect it during the economic downturn after 9/11.

The couple also endowed 24 professorships in nursing, medicine, the arts, and other areas, and multiple student scholarships.

University officials said they understood that her death might end such grand-scale giving by the Annenberg family.

"We never counted on that level of giving continuing," Penn president Amy Gutmann said. "We were blessed by the fact she gave until the very end of her incredibly long and productive life. So the loss is really the loss of Lee, more than anything else."