By Champ Clark
May 24, 2010 12:00 PM

Lena Horne didn’t mince words when discussing the trailblazing contract she signed with MGM Studios in 1942 at age 25. “I was a test case for Hollywood,” Horne told PEOPLE in 2005. “And I was a test case for audiences. Would they accept a black woman who wasn’t a servant or a native girl or a prostitute type singing a song in an all-white movie? It really seems silly now.”

That Hollywood gradually ditched such stereotypes is in large part a credit to the indomitable Horne. In movies, in song and in politics, the fiercely beautiful star commanded attention. “Lena Horne was breaking ground just by breathing,” Halle Berry told PEOPLE of the performer, who died of heart failure in New York City on May 9 at the age of 92. “For the first time everyone looked at an African-American woman and really considered her beautiful and powerful. It was empowering.” From her pioneering work in 1940s Hollywood to her triumphant one-woman show on Broadway four decades later, Horne’s incandescent looks were accompanied by an incontestable talent. “To watch Lena perform was simply breathtaking,” says her biographer Richard Schickel. “She was like a tiger. To see her in person was a transforming experience.”

The Brooklyn-born daughter of a stage-actress mother and a father who left when Lena was 3, Horne traveled the country with her mom, sometimes placed under the care of others, including her grandparents. “It was a mood of loneliness,” she later said. In 1934, at 16, she landed a spot as a chorus girl at Harlem’s Cotton Club, where stars such as Duke Ellington and Cab Calloway performed for “whites-only” audiences. In 1937 Horne briefly left show business to wed Pittsburgh political operative Louis J. Jones, the father of her daughter Gail and son Teddy. By 1940 the marriage was over, and she headed to Los Angeles. There she became a nightclub headliner and won a studio contract. “She became the first black woman to be fully glamorized and publicized by Hollywood,” says film historian Donald Bogle.

Still, racism blocked her ascent. Despite starring roles in two musicals, Cabin in the Sky and Stormy Weather, Horne was often regulated to cameos and isolated from white castmates. “They didn’t know what to do with me,” she later said. “Every scene I was in was shot to be cut out in the south.” Says Schickel: “She was like a butterfly pinned to one of MGM’s pillars. She was badly used by the studio.”

Even so, Horne became a pinup for black soldiers during WWII and famously refused to perform in USO shows when she saw African-American soldiers treated unequally. She broke barriers in her personal life too: In 1950 Horne received threats after revealing her marriage of three years to Lennie Hayton, a white composer-arranger. A fighter who overcame several tragedies-in 1970 her son Teddy died of kidney disease; Hayton died the following year-she scored a 1981 Tony Award for her soul-baring one-woman Broadway show Lena Horne: The Lady and Her Music. “I began to think about myself, to look back at what I had been given and what I hadn’t had,” Horne told the Chicago Tribune of that time. “I didn’t ever think that I should be anything but perfect for the audience. I found out along the way that they like you a little imperfect.” In life Horne could eventually accept imperfection, but never inequality. Says Berry: “That was the very big statement that Lena Horne made, just by being who she was.”