In February 1829 a ship left Baltimore for Liberia, bearing as passengers a group of freed slaves. Among them was an old man, famous from Natchez to Boston, whose passage had been paid by the government. For him it was a voyage to a home he had not seen since 1788.

He was Abd al-Rahman Ibrahima, and his story has been reconstructed with skill, style, and scrupulous research - in Mississippi, Washington, London, Paris, Africa - by a young whit historian. The first quarter-century of Ibrahima's life must in part be taken on faith, on the word of the man himself. He was probably a son of Ibrahima Sori Mawdo, king of a West African cattleherding people, the Muslim Fulbe, who had invaded and conquered the territory of Futa Jalon (now part of the Republic of Guinea).The Fulbe were brave and intelligent, tall and beautiful in their loose robes, turbans, and long braids, and Ibrahima had been reared as a Muslim aristocrat.

Born in 1762, one of perhaps 33 sons, he had a standard Muslim education in the Qur'an, and at 12 was sent abroad for five years' further study before going into the army. "Abroad" was Timbuktu, where the boy studied geography, astronomy, calculations, religion, and law. Fifty years after, two Americans, one a scholar of sorts, judged him "well versed in Oriental literature." When he was 19 something odd happened. An Irish ship's surgeon named Cox got lost during a shore expedition and was found by teh Fulbe half dead. After a long, agreeable visit as Sori's guest, Cox left Africa with gifts of gold and good wishes.

Seven years later, Ibrahima left Africa in chains.Captured in battle, he attempted in vain to buy his freedom, and was sold to native traders for muskets, gunpowder, tobacco, and rum. His final destination was Natchez, where he was sold with a fellow Fulbe to a young farmer named Foster, owner of 1000 acres of wilderness and one adolescent slave.

Ibrahima offered his new owner a great ransom. Foster, says the author, "could have been no more surprised if Ibrahima had expressed a desire to enter Harvard College and study for the ministry." His one concession was to give him the name "Prince" along with new clothes and a haircut. To remove the hair, a token of manhood and status, he had to be tied to a tree. There was worse. It was degrading to be the slave of an infidel, but for a Fulbe aristocrat to do manual work was unthinkable. He refused, was repeatedly whipped, and after a few days vanished.

Weeks later he appeared at the door. Mrs. Foster smiled and approached to shake his hand.Stretching himself on the floor, Ibrahima put her foot on his neck. It was the act of a vanquished warrior. There was no punishment and from that day, someone wrote, "Prince was a faithful, loyal servant and, I may add, trusted and beloved."

He had accepted slavery, but not as he had known it in Futa Jalon, where the basis of slavery was not racial but religious, and slaves had certain rights. Here there were no rights, but Muslims enjoyed certain advantages: they got plum jobs - drivers, overseers, confidential servants - out of proportion to their numbers; for it was a matter or religious principle to be sober, honest, and self-disciplined. Ibrahima was all this and more: his master "well knew the Negro to have an education superior to most white people," a journalist wrote later. But he was cut off from all intellectual stimulation. Until he set off on his travels 40 years later, he never saw a Qur'an, though he used to write Arabic in the dust with a stick. He spoke English haltingly, and could neither read nor write it.

Prince's life was to be passed cultivating cotton (women's work in Africa), looking after cattle, horses, pigs (an indignity for a Muslim), and selling produce at market. Once he was recognized in market by an African who cried out his real name and prostrated himself.

In 1807 he met another man who knew him. Ibrahima was selling yams when he noticed a one-eyed man on horseback. He approached with his basket; the two studied each other and the rider began to question the slave. Did he come from Africa? Was his name Abduhl Rahahman? And, "Do you know me?" "Yes, I know you very well. You be Dr. Cox." The reappearance of the ship's surgeon a quarter-century after his African so journ seemed a miracle, but when he offered to buy Ibrahima and send him home, he found himself talking quixotic nonsense to a planter who was not about to part with an exemplary and valuable slave.

Another of Ibrahima's white friends, a Natchez newspaper publisher, encouraged him to write a letter home, and in 1826 Prince set down a passage from the Qur'an, all he could remember how to write. It was sent to a senator with a somewhat confused covering letter describing Prince as a member of the royal family of Morocco. Letter and text were forwarded to the U.S. consul in Tangier, and presented to the Emperor, who at once indicated his desire that this Muslim, whoever he was, be set free and sent to Morocco at royal expense. The matter went to the Secretary of State Clay, who recommended to President Adams "the propriety of a purchase of the slave & of sending him home." Adams was agreeable, and Foster consented, on condition that it cost him nothing and that Prince should not enjoy liberty in the U.S.

In 1828, after 40 years of slavery, Ibrahima was again free, and at the last minute. Foster was persuaded to part with Ibrahima's wife too: their children and grandchildren watched them go with a "look of silent agony in their eyes." The homeward journey was to pass through Washington. Hoping to raise money to buy freedom for all his progeny, Ibrahima was outfitted in a white pantaloons, and yellow boots. In Cincinnati he paraded the streets collecting money, and again in Baltimore and Washington, where he had a ceremonious meeting with President Adams in the White House.

There was one difficulty. It was now plain that Ibrahima was not a Moroccan, did not wish to go to the Emperor's court, nor indeed anywhere until he could secure his children's freedom. A more appropriate African destination might be the new colony of Liberia, to which the American Colonizatioin Society was eager to return as many Negro Americans as could be persuaded to go. The Society thought Ibrahima a prepossessing ambassador - the Liberian colony, Africa itself, might benefit form his return with his family - and it took up the cause that had begun to embarrass the government, starting a subscription to buy up the children and grandchildren. Ibrahima made impressive appearances in Congress, presenting his subscription book to various committees. President Adams, however, ungraciously declined to subscribe. Ibrahima's take in Washington was under $500.

With a letter of commendation from Clay, he set off on a round of northern cities. Philadelphia, New York, and Boston were alive with debate of the slavery question, and the press gobbled up what scraps it could find about Africa, the Niger, Timbuktu; but Ibrahima, who could have given them volumes of firsthand information, was largely ignored. A tall gray man with a cloud of wavy white hair, wandering the streets with his costume and subscription book, he was to some a figure of fun. But in Boston the black community received him proudly with a banquet and parade, and in Hartford he encountered a venerable freed slave, a fellow Fulbe, who had fought in battles long ago under Sori's command.

In Hartford Ibrahima also met one of his most effective supporters, Thomas Gallaudet, the founder of American deafmute education. Africa was one of his many causes. At a public meeting in New York Ibrahima sat on stage looking skeptically dignified (an artist present did a pencil portrait) while Gallaudet fervidly appealed to the audience's Christian charity and its pocketbooks, summoning up a vision of the future in which Prince's return to Africa would lead to that benighted land's taking her stand among the nations of the earth, Egypt irradiating Greece with the light of wisdom, Carthage rising in new glory from the ashes. There was much applause.

In one part of the country the news of Ibrahima's travels caused more consternation than applause. His old owner was indignant that the condition he had stipulated in freeing Prince had been outrageouly flouted: if Ibrahima were to make a triumphal return visit to Natchez he would be returned to slavery at once. Southern newspapers wrote of slaves "revelling in white blood," called Adams and Clay "the emancipating Administration" and Ibrahima "their travelling emancipator." But the Adams-Clay administration was about to give way to that of Jackson, no abolitionist, and Ibrahima's well-wishers urged him to be out of the country without further delay. With his wife, but without children and grandchildren, he took his leave of America.

The arrival in Monrovia was a letdown. The houseframe the Society had provided was appropriated by another passenger; a bamboo shelter was his only protection from the rain. Funerals became the chief distraction of the African spring as the immigrants took fever and died. Ibrahima dictated a letter to a friend in New York, "I beg you not to mention to come to Africa, you must stay where you are, for the place is not fit for such people as you." He himself intended to be off to Futa Jalon as soon as the rainy season ended to interest his people in trade with America. Home was only 15 days' journey distant, but before the rains were over, Ibrahima too was dead of fever.

His tour had not been all in vain. Out of the funds he raised - about $3,500 - the Society was able to buy two of his sons and several grandchildren; they were sent to Liberia in 1830. But another son and his family remained slaves in Mississippi and vanished from history along with the Foster family and its great plantation long before the real emancipating administration came to office.

Since he was illiterate in English, Ibrahima could leave no written records and remains something of a lay figure, dignified and distant. But there are a number others whose lives touched his about whom more should be written - the brilliant mulatto John Russwurm, who was Hawthorne's college classmate and an early immigrant to Liberia; Cyrus Griffin, an intelligent and excitable lawyer, Gallaudet, even the Foster family, whose lives might have been invented by Faulkner. The book has copious and fascinating notes that lay all the cards on the table but, shamefully, no index.