Eli Broad, a self-made billionaire who amassed separate fortunes in home building and financial services, became one of the country’s most prominent philanthropists in the arts, sciences and education, and had an indelible impact on the cultural life of his adopted home city, Los Angeles, died April 30 at a Los Angeles hospital. He was 87.

Suzi Emmerling, a spokesperson for the Eli and Edythe Broad Foundation, confirmed his death but did not cite a specific cause. He reportedly had prostate cancer for more than a decade.

A power broker who saw himself as a civic-minded version of the hard-charging Gen. George S. Patton, Mr. Broad created two Fortune 500 companies from scratch: what is now KB Home, a home-construction colossus, and SunAmerica, a subsidiary of insurance giant AIG.

His fortune enabled Mr. Broad (rhymes with “road”) to pursue a second career as a philanthropist, with wide-ranging donations to medical research, public charter schools and cultural organizations. Mr. Broad and his wife, Edythe, accumulated one of the world’s greatest collections of postwar art and set up the Broad Foundations to run the couple’s charities. The foundations gave away or pledged about $4 billion by the time he retired from public life in 2017.

In Los Angeles, Mr. Broad sought to transform the city from a fractured, sprawling metropolis into “one of the four cultural capitals of the world,” alongside New York, London and Paris. He left such an outsize footprint on the region that, according to Los Angeles magazine, he was said to have more power than the mayor, more art than the world-class J. Paul Getty Museum and “more money than God.”

A 2003 cover of the magazine pointedly asked, “Does Eli Broad own LA?”

He injected hundreds of millions of dollars into the artistic life of the city, including more than $50 million to Los Angeles County Museum of Art; more than $30 million to the Museum of Contemporary Art in Los Angeles; more than $20 million to underwrite the Richard Meier-designed Eli and Edythe Broad Art Center at UCLA; and millions more to endow arts programming at Santa Monica College and to stage the Los Angeles Opera’s first production of Richard Wagner’s costly and challenging “Ring” cycle.

He helped fund charter school networks and medical research and was a major contributor to the Democratic Party. He reluctantly admitted to leading a “Democrats for Nixon” group in 1972, but in later years his art-filled home in the Brentwood neighborhood of Los Angeles became a way station for any Democrat aspiring to local or national office. He and other Los Angeles grandees used their pull to have Los Angeles host the 2000 Democratic National Convention.

“He’s like the city father that everybody wants to have,” artist Ed Ruscha told Vanity Fair magazine in 2006. “I try to imagine what that guy’s agenda is like — it must be nerve-racking. But as they say, somebody’s got to do it, and he stepped up.”

Mr. Broad was called a “white knight and lightning rod” in the Los Angeles Times, which noted the trail of bruised egos left in his wake from his domineering style. “I didn’t train in the diplomatic corps,” he liked to say. He sometimes treated wealthy board members like low-level employees, and he sometimes yanked his support for projects when he felt he wasn’t getting his way or when people receiving his largesse didn’t measure up to his expectations. He titled his memoir “The Art of Being Unreasonable.”

He infuriated renowned architect Frank Gehry by breaking an agreement to give Gehry a free hand in designing a house that would showcase Mr. Broad’s art and be a work of art itself. Maintaining that Gehry was taking too much time, he paid the architect’s design fee, then hired a different firm to build the house.

Later he had another falling out with Gehry, who was hired to design a new home for the Los Angeles Philharmonic. The new building, the Walt Disney Concert Hall, also was to be the keystone of Grand Avenue, a downtown thoroughfare that Mr. Broad had long wanted to turn into Los Angeles’s answer to Fifth Avenue and the Champs-Élysées.

After soaring costs and years of delays on the project, Los Angeles Mayor Richard Riordan (R) settled matters in 1996 by telling Gehry and Disney heirs, “There’s only one person who can make this happen, and that’s Eli Broad.”

Chafing at the stalled project that he attributed in part to Gehry, Mr. Broad said the city’s reputation was at stake, fearing that the project could become a laughingstock among arts aficionados in other cities.

Many in Los Angeles power circles credited him with rescuing the project from failure. He contributed $18 million of his own money and solicited tens of millions of dollars from other corporate executives, persuading them that “a piece of architecture could become a rallying point for people to work together.”

Given broad authority over the plans — which caused Gehry to threaten withdrawing from the project — Mr. Broad dispensed with consultants and what he considered other wasteful expenditures.

“There was no one on top saying, ‘Wait a minute — what’s that going to cost?’ ” Mr. Broad told Los Angeles magazine. “Disney Hall had been on the cover of the New York Times Magazine and all these architectural journals, and if we didn’t get this done, it would show everything that was wrong with Los Angeles, with its political leadership, civic leadership, corporate leadership, et cetera.”

Disney Hall was finally finished to great acclaim in 2003, and Gehry reconciled once more with Mr. Broad.

“You’ve all heard that Eli and I have been at each other, but look at what we’ve built,” Gehry said, toasting the new building. “The result is beautiful, and we’re both proud of it.”

A patron of schools and the arts

Eli Broad was born in the Bronx on June 6, 1933, to Jewish immigrants from Lithuania. He was 6 when his family moved to Detroit, where his mother worked as a dressmaker and his father painted houses and operated five-and-dime stores.

In 1954, he graduated from Michigan State University — completing his studies in three years — and married Edythe Lawson. After working as an accountant, he launched Kaufman & Broad in 1957, with his wife’s cousin Donald Kaufman, a Michigan developer. The houses were rudimentary, with no basement, but they were cheap and sold well.

“We built a model that I named the Award Winner, although it won no awards except for the award I gave it,” Mr. Broad told the Los Angeles Times. “We listed it for $11,990, and our competitors, who were fat, dumb and happy, were selling their models with basements for $15,000.”

By 1963, when Kaufman retired, Mr. Broad was a multimillionaire and had settled in Los Angeles. Eight years later, he paid $52 million for SunAmerica, an insurance company specializing in annuities, and it became one of the fastest-growing stocks on the New York Stock Exchange. Insurance giant AIG bought the company in 1999 for $18 billion, with Mr. Broad’s share coming to $3.4 billion. In 2017, the New York Times estimated his wealth at $7.3 billion.

Like Microsoft co-founder Bill Gates, Mr. Broad spent a large part of his fortune on education and insisted that recipients of his donations meet strict performance criteria. Each year from 2002 to 2014, he awarded the $1 million Broad Prize for Urban Education to an improving urban school system, but all the winning schools slid back into mediocrity, and he suspended the prize. Mr. Broad eventually focused more on training school administrators and developing charter schools.

Mr. Broad said he owed his involvement with contemporary art to his wife, who began to visit art galleries in the 1960s. The couple’s first major purchase was a drawing by Vincent Van Gogh for $95,000. When a friend complained that he paid too much for it, Mr. Broad responded, “I’ll listen to your advice about quality, but not about price.”

Eventually, the Broads began to collect works by — and befriend — such artists as Jeff Koons, Roy Lichtenstein, Jasper Johns, Robert Rauschenberg and Cindy Sherman. Their home became a de facto museum.

He presented a $60 million gift to the Los Angeles County Museum of Art to finance the Broad Contemporary Art Museum, designed by Renzo Piano, which opened in 2008. The Broads later built a separate Los Angeles museum of contemporary art to display much of their collection. That museum, known simply as the Broad, opened in 2015 across the street from Disney Hall.

Mr. Broad also gave tens of millions of dollars to other institutions, including Michigan State University, Harvard University, the California Institute of Technology, the Massachusetts Institute of Technology, the University of California at Los Angeles and California’s Pitzer College. He was on the boards of Los Angeles-area museums and organizations as well as the Museum of Modern Art in New York and the Smithsonian Institution in Washington.

For years, Mr. Broad tried in vain to buy the Los Angeles Times from its corporate owner in Chicago and to lure a National Football League team back to Los Angeles, after the Rams and Raiders left the area in the mid-1990s. Another billionaire, Patrick Soon-Shiong, bought the Times in 2018, and other wealthy owners brought the NFL back to Los Angeles in 2016.

Mr. Broad’s survivors include his wife, the former Edythe Lawson of Los Angeles; and two sons, Jeffrey Broad and Gary Broad.

For all the splendor of his home, with its Rauschenbergs on the walls and a Richard Serra sculpture on the lawn, Mr. Broad led a life of modest tastes. On his private Gulfstream jet, he saved money by not having a private chef.

Instead, he bought sandwiches from a food service and handed them out to his guests, unwrapping them himself and serving them on paper plates.