Eartha Kitt's daughter has revealed that the singer died without knowing the identity of her white father, after being denied the truth by officials in the American Deep South.

Kitt's extraordinary life and elusive past has come under the spotlight five years after her death, with publication of a biography called America's Mistress: Eartha Kitt, Her Life and Times by British journalist John Williams.

The world-famous singer came from a dirt-poor background and only found out her date of birth when she was 71. But according to her daughter, Kitt Shapiro, who chose not to co-operate with the biography, when Eartha launched a legal fight to gain access to the birth certificate she fell victim to a cover-up by officials. The singer, who died in 2008, wept when she set eyes on the certificate in 1998, only to find that her father's name had been blacked out, said Shapiro, her only child, who had accompanied her mother. Shapiro said in an interview with the Observer: "My mother was 71 at the time and it was approaching the 21st century, and yet they were still protecting the name of the father even though he was clearly dead. They were protecting the white man because they would not have gone to that trouble to protect a black man. The courts still held it as legal to withhold the documentation. We were amazed. My mother assumed it was their dirty little secret."

Once called the "most exciting woman in the world" by Orson Welles, Kitt became a singer and dancer whose suggestive and sensuous performances captured the public imagination in the 1950s. Her former lover Charles Revson, the billionaire founder of Revlon cosmetics, even created a lipstick for her, calling it Fire and Ice. In the 1960s she made the role of Catwoman her own when she became the first black woman to achieve mainstream TV success in America with Batman, even breaking racial taboos by flirting on screen with Adam West in the lead role.

Much of Kitt's background remained shrouded in mystery, with the performer convinced that her date of birth was 26 January 1926. Born in the tiny hamlet of St Matthew's, South Carolina, Kitt's mother, Annie Mae Keitt, abandoned her daughter at an early age when she found a new man with little time for the light-skinned Eartha.

Shapiro, who now lives in Connecticut, said: "In 1927, to be a light- skinned black person in the South was just as horrible as being a black person in the white South. My mother was not accepted by the black community.

"She never found out her father's name, but always assumed he was white. My mother was referred to as a 'yellow gal', which was not a compliment. It meant someone who thought they were better than everyone else even though my mother was just a child at the time. She was horribly abused in the South. She was beaten, mistreated, emotionally and physically."

Eartha Kitt was taken in by a relative called Aunt Rosa, but far from finding sanctuary fell victim to her abusive relative and from a young age was obliged to earn her keep by picking cotton. But the horror did not end there because she witnessed the death of her mother when she was around seven years old.

Shapiro, 51, said: "She was convinced her mother was poisoned. My mother remembered being brought to her mother who was dying and a baby was passed over her mother's body. My mother's interpretation was that this was because the death was not natural: it was voodoo. It was spiritual."

Soon after her mother's death, Kitt was sent to live with another relative in New York, where she would later win a place with America's first black modern dance company, run by Katherine Dunham. During the company's tour to Paris and London, Kitt broke away to make a solo career and Britain would become a second home for Kitt and her daughter. But it was only when Kitt was invited to give a speech at Benedict College in Columbia, the capital of South Carolina, in 1997 that the singer managed to come to terms with her original home.

Shapiro said: "It was like much of my mother's life: it was just a case of a door opening. She was invited to speak at this college and I went down with her. During the speech someone asked her about her background and parents since she was from the area. My mother said that she had tried to find her birth certificate during the 1950s but was unsuccessful.

"She said if anyone can find it, then she would be most grateful. So the kids found some information that eventually led us going back down to the South."

She added: "We had to get a lawyer and petition the court to get the records opened and this took about six to seven months. We flew down to see the records but were allowed just 15 minutes … She was very nervous and outside the judge's chambers she went quiet. She was visibly nervous about what she was going to see. I knew the signs because before she went on stage she was always terrified. It was a female judge who stepped aside while we read the records on her desk. The father's name was blacked out. My mother shed a few tears and then the 15 minutes was up."

Williams claims that Kitt's father was Daniel Sturkie, a local white doctor. But Shapiro said: "I do remember the name because we were told they were one of the local white families, but I cannot recall whether it was suggested he was the father. There were a lot of names."

Shapiro, who worked for her mother for more than 20 years, believes that this failure to find out her mother's origins explains her tortured relationship with the South and her own identity. "My mother never really felt comfortable in her own skin because she never really knew who she was until then. She did not even know how old she was. She had always put 26 January 1926 on her passport, but actually she was born on 17 January 1927."

Kitt became a leading light in the civil rights movement in the 1960s but when she condemned the Vietnam war on a visit to the White House her career in the US ended and the CIA branded her "a sadistic nymphomaniac". By then Kitt had divorced the father of her daughter, Bill McDonald, who was a white businessman and wounded Korean war veteran addicted to painkillers, and mother and daughter moved to London to relaunch her career in Europe. Shapiro said: "We lived in Knightsbridge and later Fulham. I went to school in London and spent many a year in England. My mother regarded England as a second home."

In 2008 Kitt died on Christmas Day at her US home after being diagnosed with colon cancer. Now her daughter has set up a business called Simply Eartha in her mother's memory, as well as managing her estate. She said: "She carried the scar of her rejection with her all her life. She was rejected for the colour of her skin ironically by both black and white.

"To some extent, I think my arrival completed her because it gave her a family that she never had."