Although a legendary figure in New York City and feted with a famous gala on her 100th birthday in March 2002, Mrs. Astor was mostly interested in putting the fortune that her husband, Vincent Astor, left to use where it would do the most to alleviate human misery.
Her efforts won her a Presidential Medal of Freedom, the nation's highest civilian honor, in 1998.
"Money is like manure; it should be spread around," was her oft-quoted motto. There was a lot to spread: Vincent Astor's great-great-grandfather John Jacob Astor made a fortune in fur trading and New York real estate.
Mrs. Astor gave millions of dollars to what she called the city's "crown jewels," among them the New York Public Library, Carnegie Hall, the Museum of Natural History, Central Park, the Bronx Zoo, and the Metropolitan Museum of Art, where the flags were lowered to half-staff after her death.
But she also funded scores of smaller projects: Harlem's Apollo Theater, a new boiler for a youth center, beachside bungalow preservation, a church pipe organ, and furniture for homeless families moving into apartments.
It was a very personal sort of philanthropy.
"People just can't come up here and say, 'We're doing something marvelous, send a check,' " she said. "We say, 'Oh, yes, we'll come and see it.' "
The final year of Mrs. Astor's life was marred by a nasty family feud over her care, including allegations that the grand dame of society was forced to sleep on a couch that smelled of urine while subsisting on a diet of pureed peas and oatmeal. Court papers said her beloved dogs Boysie and Girlsie were kept locked in a pantry.
The allegations emerged in July 2006 court documents that provided a daily source of sensational headlines. In a settlement three months later, her son, Anthony Marshall, was replaced as her legal guardian with Annette de la Renta, wife of the fashion designer Oscar de la Renta.
Marshall's son -- Philip Marshall, a professor at Roger Williams University in Rhode Island -- had alleged that his father was looting her estate and allowing her to live in the filthy conditions at her Park Avenue duplex.