Nearly 600 years after she was burned at the stake, Joan of Arc is still making headlines. This past April, forensic scientists at Raymond Poincaré Hospital in Garches, France, announced in the journal Nature that relics supposedly found beneath her pyre are a forgery. The remains, which included a human rib, were never burned, and instead show evidence of embalming. Using carbon-14 analysis, the researchers dated the fragments to between the third and sixth centuries B.C. They concluded that the relics were taken from an Egyptian mummy, a component, in powdered form, of some medieval pharmaceuticals.

Found in the attic of a Paris apothecary in 1867, the manufactured relics date to a time when history was rediscovering Joan of Arc, and they were probably created to add to the mystique of the French martyr. The scheme may have been effective, since shortly afterward, in 1869, the Catholic Church took the first step toward Joan's 1920 canonization as a saint. The Church, which in 1909 had recognized the relics as likely genuine, accepted the 2007 study's findings. But though this tantalizing fragment of Joan of Arc has been proven a fake, her legend carries on.

Much of what we know about Joan of Arc comes from the transcript of her 1431 trial for heresy—an inquisition that resulted not only in her execution but also assured her immortality as a French heroine and Catholic martyr. In 1455, additional testimony from a posthumous retrial (requested by King Charles VII and Joan's elderly mother, and authorized by Pope Calixtus III) restored Joan's reputation and fleshed out her story. Thanks to these records, Joan's narrative is remarkably complete.

Born into a farming family in Domrémy, in northeastern France, probably in 1412, Joan lived the average life of a peasant girl. (It is a common misconception that Joan came from a place called "Arc," but "d'Arc," which translates into English as "of Arc," was only a surname.) "I worked at common tasks about the house," Joan said of her childhood. "I learned to sew and spin.... I learned my faith, and was rightly and duly taught to do as a good child should." Meanwhile, France had been at war with England on and off since 1337. The conflict, now known as the Hundred Years' War, stemmed from English King Edward III's attempt to claim the French throne. By the 15th century, the English occupied much of France, and with their French collaborators they prevented the Dauphin Charles, the French crown prince, from being installed as king upon his father's death in 1422.

When Joan was 13, she began to hear voices. She identified the speakers as Saint Michael, the Archangel, and Saints Catherine and Margaret, two early Christian martyrs who, like Joan, had been virginal teenagers. God had given Joan a mission, the voices said. The young woman had to fight the English occupation and help Charles become the legitimate king of France. By 1428, when Joan was about 16, the voices had become so adamant that she felt she had to do what they asked, despite the apparent impossibility of the task.

Joan went to the nearby town of Vaucouleurs and introduced herself to Charles' soldiers. Though the garrison captain promptly sent her home, Joan's voices insisted that she complete her divine mission. She returned in January 1429 and this time talked her way to the French court, where she was able to convince the prince—who was desperate for whatever help he could get—to take her seriously.

Charles provided troops for Joan to command, and in the battles that followed, she was more than a figurehead—she actually fought. Though she claimed never to have killed a man herself, Joan at one point praised the "good war-sword" that she carried, explaining that it gave "good buffets and good thrusts." Guided by her supernatural voices, she led the fight to free the city of Orléans from the English siege. After several more battles, Joan had cleared the way for the Dauphin to be crowned at Reims, the traditional site of coronations. In July 1429, the prince became King Charles VII. Joan continued to fight the English.

Before a battle to capture the town of Jargeau in June 1429, Joan roused her troops with the exhortation, "Fear not.... God guides our work. Were I not certain that God guides this work, I would rather keep sheep than expose myself to such perils." As it turned out, Joan exposed herself to more peril than she could have imagined.

In May 1430, she was captured by French collaborators, who sold her to the English for the sizable sum of 10,000 francs. Joan spent the next year imprisoned in the city of Rouen, in northwest France. In their efforts to convict her of witchcraft, a crime that would warrant her execution, the English and their French partisans subjected Joan to months of intense interrogation. But the young woman retained her poise throughout the ordeal, and her captors could not prove witchcraft. Forced to sign a confession, Joan at first received a life-sentence for non-capital heresy. Shortly afterward, the authorities condemned her to death on a technicality: that she continued to wear men's clothes, despite being warned that it was a sin. Evidence suggests that she was set up—someone may have taken her women's clothes and left her with nothing else to wear. Joan was burned on May 30, 1431.

The detailed trial transcripts reveal a remarkably human saint, and the story invites modern interpretation. Today, scientists routinely propose medical and psychiatric explanations for Joan's voices. The diagnoses range from inner ear diseases and brain tumors to schizophrenia and psychopathy. One popular theory, proposed in a 1991 paper published in the journal Epilepsia, says that Joan had "ecstatic epileptic auras."

But whether or not her voices were mere hallucinations, writes biographer Donald Spoto, author of Joan: The Mysterious Life of the Heretic Who Became a Saint (2007), she lived at a time "when faith was a fact of life." Mental illness (though not its cause) was recognized in 15th-century Europe, and not all claims to divinity were accepted as such. Charles VII's father, for example, had believed that he was made of glass, and his subjects recognized that he was delusional. But Joan of Arc, with her charisma and confidence, convinced much of France that her voices were actually messages from God.

Despite modern efforts to debunk her, Joan of Arc retains her status as a religious and patriotic heroine, especially in France. Since the 19th century, when nationalism became a major theme in Europe, books, plays and operas about Joan have abounded. Her popularity continued into the 20th century and beyond: she has been the subject of more than two dozen films, as well as popular songs, video games and TV shows.

Joan's name and face have been used to promote everything from faith and feminism to goat cheese and canned beans. ("Joan of Arc was an amazing woman—she lived and died for her beliefs," states the Web site for Joan of Arc brand beans. "We think Joan would have been proud of the beans that bear her name.") During the two World Wars, Joan appeared in American, British and French propaganda. The Vichy government used her martyrdom to condemn the English—who, the Nazi collaborators pointed out, burned the French heroine. Never mind that Hitler had invaded France.

More recently, French politicians of every party invoked Joan's name during the closely watched presidential campaign leading up to the elections of April 22 and May 6, 2007. Perennial far-right candidate Jean-Marie Le Pen, calling Joan "the eternal symbol of French patriotism," appropriated her as an emblem for his nationalistic party, the Front National. Meanwhile, at the other end of the political spectrum, socialist Ségolène Royal, the only woman among the top presidential candidates, called Joan her political role model. An underdog in the polls, Royal compared herself to the heroine of France, fighting against daunting odds for the sake of her people.

It is a testament to Joan's universal appeal that both the left and the right can still earn applause by praising Joan of Arc. In an April 25 speech at Rouen, the site of Joan's execution, the future French president Nicolas Sarkozy decried appropriation of Joan's name. "Joan rises above all the parties, and no one can hijack her," the candidate said. "Joan is France!"