LOS ANGELES: Esther Williams, whose experiences as a young swimming champion led to a career of Hollywood "aqua-musicals" designed just for her, died on Thursday in Beverly Hills, California, at the age of 91, her spokesman said.

Williams, one of the biggest box-office stars of the 1940s and 1950s, died peacefully in her sleep and had been in declining health due to old age, spokesman Harlan Boll said.

Williams became known as "Hollywood's Mermaid" and "The Queen of the Surf." At her peak, the woman with the wide smile and bright eyes was second in earnings only to Betty Grable and often in the top 10 box-office draws.

Williams' aqua-musicals were escapist comedies in lush color, with lavish song and watery dance numbers and lots of footage of synchronized swimming. They were so popular that some credited her with a jump in the popularity of home swimming pools.

A typical finale featured Williams diving into a pool or lagoon and surfacing to a crescendo of music with waterdrops glistening on her smiling face and sleek body.

She dismissed her talent, saying "I can't act, I can't sing, I can't dance. My pictures are put together out of scraps they find in the producer's wastebasket."

But after watching the films decades later, she softened that self-deprecating assessment, saying: "I look at that girl and I like her. I can see why she became popular with audiences. There was an unassuming quality about her. She was certainly wholesome."

Williams was born in the Los Angeles suburb of Inglewood on August 8, 1921. As a young swimmer, she set what were then world records in the 100-meter freestyle and 880-yard relay. She also worked as a model.

With future "Tarzan" star Johnny Weissmuller, Williams began appearing in Billy Rose's Aquacade live water shows, where she attracted the attention of MGM movie executives. She married pre-med student Leonard Kovner and turned down movie offers for a year.

WARTIME PINUP TO 'BATHING BEAUTY'

Williams eventually signed with MGM but begged out of her first planned job, a straight acting role opposite Clark Gable, claiming she was unprepared.

Williams hit the water in her first film, "Andy Hardy's Double Life" (1942) but stayed out of it for "A Guy Named Joe" (1943), the first of five movies she made opposite Van Johnson.

It was the pool - and wartime pinup pictures of her in bathing suits - that made her popular. She returned to the water for "Bathing Beauty" (1944) and "Ziegfeld Follies (1946), both of which featured Williams in water ballets. In "Thrill of a Romance" (1945), the basic plot of most of her movies was established as she played a swimming instructor who falls in love.

Her out-of-the-water roles were generally less successful. "Wet, she is a star," comic Fanny Brice once said. "Dry, she ain't."

As the public's fascination with water sports slipped and Williams moved into more dramatic roles, her popularity fell.

In 1945, a year after divorcing her first husband, she married Benjamin Cage, a former radio announcer who was influential in establishing an Esther Williams line of bathing suits, swimming pools, restaurants and other commercial ventures. She had three children with Cage before they divorced.

In 1961 she co-starred with Fernando Lamas in the circus movie "The Big Show" and they were married in 1969. She wrote in her autobiography, "The Million Dollar Mermaid," that Lamas was so controlling that he refused to let her children come to their house.

Lamas died in 1982 and Williams married actor Edward Bell in 1994.

In her later career, Williams did a few 1960s television specials and hosted swimming events for ABC-TV's coverage of the 1984 Olympic Games.