Emily Fisher Landau, a New Yorker who used a Lloyd’s insurance settlement from a spectacular jewel heist in her apartment to fund what would become one of America’s premier collections of contemporary art, died on March 27 in Palm Beach, Fla. She was 102.

Her death was confirmed by her daughter, Candia Fisher.

From 1991 to 2017, Ms. Landau opened her collection of 1,200 artworks to the public in the Fisher Landau Center for Art, a repurposed former factory in Long Island City, Queens. In 2010, she pledged almost 400 works, then worth between $50 million and $75 million, to the Whitney Museum of American Art, where she had long been a trustee.

Ms. Landau’s trajectory into the art world began unexpectedly on a spring afternoon in 1969, while she was out at lunch. Armed burglars disguised as air conditioning repairmen broke into her apartment in the Imperial House building on the Upper East Side, bound the cook in a guest closet and opened a floor safe hidden inside another closet.

For birthdays, anniversaries and holidays over the years, her husband, Martin Fisher, a real estate developer, had given her parures — matched necklace, earring, ring and bracelet sets holding emeralds, rubies, sapphires and diamonds — along with a 39-carat blue white diamond solitaire. All were kept in the safe.

“I was devastated,” Ms. Landau said of the heist in interviews conducted for a Whitney catalog, “Legacy: The Emily Fisher Landau Collection.” But, she added, “I decided that I didn’t want the jewelry any more. I now had seed money for a collection,” thanks to the insurance settlement.

“What I really wanted to buy was paintings,” she said, “so probably the theft was one of the best things that ever happened to me.” (The scene of the crime, Imperial House, on East 69th Street between Lexington and Third Avenues, had been built by her husband’s company, Fisher Brothers.)

Ms. Landau had aspired to become an artist before her father, also a developer, sent her to secretarial school. Later, without ever having taken an art history class, she started collecting informally. After the jewelry theft, her first major piece was a three-and-a-half foot tall Calder mobile, which she bought in 1968 from its owner on Central Park West.

“I didn’t have a car and driver in those days, and so I came back on the crosstown bus on West 86th Street and stood up and carried the Calder like a Christmas tree,” she said. “Nobody asked me anything.”

Ms. Landau soon discovered the work of Josef Albers when, walking along East 57th Street, she chanced on a poster in a window for a show at the Pace Gallery. “It startled my eye — so minimal,” she said. “From the moment I saw that Albers, I knew I loved simplicity. Albers was my beginning point as a collector. I’ve never collected something because it was fashionable. It was always about what I instinctively liked.”

Her curiosity led her upstairs to Pace and what turned out to be a long relationship with the gallery and its owner, Arne Glimcher. “Originally I bought art with my husband,” she said. Their first large acquisition was a trio of paintings — by Picasso, Dubuffet and Léger — that Mr. Glimcher had shown her, all leaning against a wall in his office. “Later I’d buy on my own,” she said.

She went on to buy works by Matisse, Mondrian, Jean Arp, Mark Rothko, Franz Kline, Paul Klee, Louise Nevelson and Lucas Samaras. “I spent all the money on art,” she said. “Those were buy years.”

Pace, along with the Leo Castelli Gallery in Manhattan, remained a major source for her growing collection, but Mr. Glimcher’s gallery partner, Fred Mueller, proved a role model for integrating art, artists and a New York social life. She remembers a party in his spare Gracie Square apartment where Ms. Nevelson, Robert Rauschenberg and Andy Warhol circulated among their own artworks with other guests. “His example actually gave me the impetus to collect in depth,” Ms. Landau said.

But then her husband died, in 1976. “After that there was a big gap in the collection,” she said. “I stopped.”

In about 1980, Ms. Landau met and hired the New York theater and restaurant designer Bill Katz to redecorate her apartment on Park Avenue, where she had since moved. The commission morphed into a long-term relationship in which Mr. Katz, also an art consultant, advised her on collecting beyond the core modernists she already had.

“‘Emily, if you want to look at younger people’s work, it would change their lives, and be an interesting experience for you,’” she recalled him telling her.

On studio visits in New York’s heated art world of the 1980s and ’90s, Ms. Landau focused on contemporary works, sometimes buying the whole room, as she did with a Rodney Graham show.

“She had the temperament to move forward with the zeitgeist,” said the New York art adviser Amy Cappellazzo. “She became well known as a major collector, and I think her tastes encouraged that moment through the ’80s and ’90s. Others followed.”

By the mid-1980s, Ms. Landau had become a trustee at the Whitney, where she sat on a succession of boards for nearly 25 years. The fourth floor of the museum, then located on Madison Avenue on the Upper East Side, was named in her honor in 1994, the year she established an endowment for the Whitney Biennial exhibitions.

“She probably has been one of the most important trustees in Whitney history,” said Leonard Lauder, chairman emeritus of the museum.

By the mid-1980s, with the art market swelling in New York and museums expanding across the country, Ms. Landau occupied an increasingly prominent place within New York’s art ecosystem, supporting artists personally and museums institutionally.

Beyond the Whitney, she sat on committees at the Museum of Modern Art and on the boards of the Georgia O’Keeffe Museum and SITE Santa Fe museum, both in New Mexico. For her support of its cultural institutions, the French government inducted her into the Order of Arts and Letters as a chevalier.

Outside the art world, she established the Fisher Landau Foundation for research on dyslexia and assistance to dyslexic children — she herself was dyslexic — and the Fisher Landau Center for the Treatment of Learning Disabilities for children, adolescents and adults at the Albert Einstein College of Medicine in the Bronx. She also had a seat on the board of the Metropolitan Opera.

In the late 1980s, Ms. Landau found a 25,000-square-foot former parachute-harness factory in Long Island City to house her collection — a private museum that would be open to the public at no charge. Max Gordon, a minimalist London architect fresh from his conversion of a paint factory into the Saatchi Collection in London, transformed the Queens plant, a three-story concrete structure, into the Fisher Landau Center for Art.

“With her own museum, she was a great example of the premier collectors in history who collect not just for themselves but for posterity,” Mr. Lauder said. “She was buying more for tomorrow than today.”

Emily Lanzner was born on Aug. 23, 1920, in Glens Falls, N.Y., near Lake George, and grew up in the Washington Heights section of Manhattan, living in Emily Court, a building her father, Samuel Lanzner, developed and owned, naming it after his daughter. Her mother, Cecilia Lanzner, was a homemaker.

After a brief marriage, she met and later married Mr. Fisher, at the time the young landlord of an apartment in which she was living in Forest Hills, Queens. She had three children with him, Richard, Anthony and Candia. In 1978, after Mr. Fisher’s death, she married Sheldon Landau, a retired clothing manufacturer. Her son Anthony and his wife, Anne, died in a plane crash in 2003. That same year, her grandson Andrew died in an automobile accident. Richard, her older son, died in 2006. Mr. Landau died in 2009.

In addition to her daughter, Ms. Landau is survived by nine grandchildren and four great-grandchildren.

With the succession of tragedies in her immediate family — all coinciding with changing markets in the art world in the 2000s — Ms. Landau’s interest in collecting diminished.

“From about 2004 to 2008, a lot of hedge fund people speculated,” the New York gallerist Barbara Gladstone said. “They were a different breed, and Emily was happy to step aside. She typifies pre-2000 collectors who made an avocation out of refining their collections. She was not just buying because it would go up in value. That’s a wonderfully old-fashioned tradition.”

Ms. Landau’s Center for Art remained open to the public until 2017. In her last years, she struggled with Alzheimer’s disease and lived primarily in Greenwich, Conn.

“Whenever she spotted a woman wearing expensive jewelry,” her daughter, Candia Fisher, said, “she used to say, ‘That could be art on the walls.’”