LOS ANGELES — Esther Williams, a swimming champion who became a Hollywood legend, has died at age 91.

She died early yesterday in her sleep, said her publicist, Harlan Boll.

Williams became one of Hollywood’s biggest moneymakers in the 1940s and ’50s, appearing in spectacular swimsuit numbers that capitalized on her wholesome beauty.

Such films as “Easy to Wed,” ‘‘Neptune’s Daughter” and “Dangerous When Wet” followed the same formula: romance, music, a bit of comedy and a flimsy plot that provided excuses to get Williams into the water.

The extravaganzas dazzled a second generation via television and the “That’s Entertainment” compilation films.

Williams’ co-stars included Gene Kelly, Frank Sinatra, Ricardo Montalban and Howard Keel.