The British supermodel had fought for months to avoid testifying and being questioned at Taylor's war crimes trial before the Special Court for Sierra Leone on the subject of "blood diamonds" - illegally mined gems used to finance wars. She had declined to cooperate with prosecutors until judges last month ordered her to appear or face a possible seven years in jail for contempt.
Entering the courtroom fashionably late - several minutes after she was first summoned to take the stand - Campbell was calm and composed as she answered questions from prosecutor Brenda Hollis for nearly two hours.
"I didn't really want to be here," she said. "I just want to get this over with and get on with my life, this is a big inconvenience for me."
Prosecutors had hoped Campbell would provide evidence that Taylor traded guns to neighboring Sierra Leone rebels in exchange for uncut diamonds during Sierra Leone's 1992-2002 civil war. Actress Mia Farrow has claimed that Taylor gave Campbell an uncut diamond or diamonds after a 1997 dinner hosted by then-South African President Nelson Mandela at his presidential mansion in Pretoria.
Prosecutors say from his seat of power in Liberia, Taylor armed, trained and commanded Sierra Leone rebels who murdered and mutilated thousands of civilians across the border. Taylor, 62, says he is innocent of the 11 war crimes charges he faces, including murder, rape, sexual enslavement and recruiting child soldiers.
Campbell arrived at the courthouse in Leidschendam surrounded by a police escort. In contrast to her usual edgy fashion style, she wore a demure cream two-piece outfit and piled up her straight dark hair into a classic chignon. The look was topped off with a silver "evil-eye" necklace.
Speaking confidently, Campbell testified that she was awakened in the middle of the night after the September 1997 dinner party by two men at her door. She said they offered her a pouch they said was a gift for her with no further explanation.
She said she frequently receives gifts from admirers and didn't look at it until the following morning.
"I saw a few stones in there. And they were small, dirty-looking stones," she said.
She said, at breakfast the following day, either Farrow or Campbell's former agent Carole White had told her the rocks must be diamonds and were probably a gift from Taylor.
Campbell said she gave the stones to a friend, Jeremy Ratcliffe, who at the time was the director of the Nelson Mandela Children's Fund, intending he use them for charity. She said she had called Ratcliffe a year ago to ask what he had done with the stones, and he told her he still had them.
Campbell's comments were the first time Ratcliffe's name had appeared at the trial.
In South Africa, a spokesman for Mandela's charity, Oupa Ngwenya, told reporters later Thursday that the fund did not receive the diamonds, noting it would have been illegal for them to do so. But he also said the fund was unable to locate Ratcliffe, now a trustee for the charity.
It was not clear where Ratcliffe was - there was no response to phone calls to his South African homes in Johannesburg or Plettenberg Bay or to his cell phone.
Hollis asked Campbell why she had been so reluctant to appear before the war crimes tribunal, and the model said she was afraid to be associated with Taylor.
"This is someone that I read up on the Internet that killed thousands of people supposedly and I don't want my family in any danger in any way," Campbell said.
Taylor's defense attorney, Courtenay Griffiths, angrily objected, saying the line of questioning was "totally irrelevant" to Campbell's testimony.
Campbell had been called to the stand by the prosecution, but she often seemed more comfortable answering questions from Griffiths, the defense attorney. Griffiths got Campbell to testify that some statements about the dinner given to prosecutors by Farrow and White were wrong. He said White has suggested that Campbell was seated next to Taylor at the dinner and flirted with him.
White is enmeshed in a legal dispute with Campbell.
"This is a woman who has a powerful motive to lie about you?" Griffiths asked.
"Correct," Campbell answered, with a slight smile. She said she sat between Mandela, whom she idolizes, and music producer Quincy Jones at the dinner.
Appearing to take great pains to distance herself from former Liberian president, she repeated several times that she couldn't verify that the stones were diamonds or that they came from Taylor.
"They were kind of dirty looking pebbles ... when I'm used to seeing diamonds I'm used to seeing them shiny in a box," she said, smiling. "If someone hadn't said they were diamonds I wouldn't have guessed right away that they were."
She said Farrow had suggested they came from Taylor, and she merely agreed. She added she has never seen Taylor before or since that dinner until her court appearance Thursday.
"I had never heard of Charles Taylor before, never heard of the country Liberia before, had never heard the term 'blood diamonds'," she said.
Both White and Farrow are to testify before the war crimes tribunal on Monday.
Frustrated by Campbell's answers, Hollis said the model appeared to be downplaying her friendliness with Taylor, pointing to a photograph in which they were standing next to each other at the dinner.
But Griffiths said it wasn't right for the prosecution to challenge the credibility of its own witness, and Judge Julia Sebutinde agreed. Hollis then argued Campbell should be considered a court witness, given that she had stonewalled prosecutors ahead of Thursday's testimony.
"You subpoenaed her and it was a prosecution witness," Sebutinde retorted.
Taylor, sitting in the defendant's chair, smiled at the exchange. In custody in the Netherlands since June 2006, he is the first former African head of state to stand trial at an international war crimes court.
International law experts said Thursday's testimony by Campbell was unlikely to affect the course of Taylor's trial. But media turnout was extremely heavy, with more reporters and television crews attending than at any time since the trial began in January 2008.
"This whole episode with Naomi Campbell being called to testify, what's welcome about that is that it's thrown the international media attention back on to the issue of blood diamonds," Global Witness spokesman Oliver Courtney told AP Television News. "This is a problem that hasn't gone away, as we see continued human rights abuses linked to diamonds in countries like Zimbabwe."
Campbell became one of the world's highest-paid models after being discovered while shopping in London at age 15. Now 40, the hot-tempered supermodel is no stranger to courtrooms, having faced a series of minor lawsuits and criminal cases over the years.
In June 2008, she pleaded guilty in an incident where she cursed, kicked and spat at police at London's Heathrow airport in a rage over a missing piece of luggage. She was sentenced to 200 hours of community service.
Campbell also did another week of community service sweeping floors and scrubbing toilets in a Manhattan garbage-truck depot in 2007 after pleading guilty to misdemeanor assault for hurling a cell phone at her maid because of a vanished pair of jeans.
In 2000, Campbell pleaded guilty in Toronto to an assault charge for beating an assistant who said the model whacked her on the head with a phone.
A few of Campbell's former aides and maids have sued her, accusing her of violent outbursts. Some cases have been settled on undisclosed terms.
Associated Press Writers Michelle Faul and Eric Naki in Johannesburg contributed to this report.