Half a century ago, inspired by the Supreme Court's decision in Brown v. Board of Education, historians embarked on an effort to identify the origins of racial segregation. C. Vann Woodward insisted that rather than existing from time immemorial, as the ruling's opponents claimed, segregation emerged in the 1890s. Others located its genesis in Reconstruction or the pre-Civil War North.

Eventually, the debate faded. Now, Nicholas Guyatt offers a new interpretation. Segregation and its ideological justification "separate but equal," he argues, originated in the early Republic in the efforts of "enlightened Americans" to uplift and protect Indians and African--Americans. After trying and abandoning other policies, these reformers and policy makers concluded that only separation from whites — removal of Indians to the trans-Mississippi West and blacks to Africa — would enable these groups to enjoy their natural rights and achieve economic and cultural advancement. Thus, almost from the outset, the idea of separating the races was built into the DNA of the United States.

Guyatt, who teaches at the University of Cambridge, is the author of a well--regarded book on the history of the idea (still very much alive today) that God has chosen this country for a special mission. In "Bind Us Apart" he addresses another theme central to our national identity: Who is an American? To find an answer he offers a detailed account of early national policies toward Indians and blacks.

By the somewhat anachronistic label "liberal" — usually applied, when referring to the 19th century, to believers in limited government, free trade and individual liberty — Guyatt means adherents of Enlightenment values, including the repudiation of prejudice against others. These people realized that the presence of subordinate racial populations could not be reconciled with the affirmation that "all men are created equal" in the Declaration of Independence. They assumed that what appeared to be black and Indian inferiority resulted from oppressive circumstances, not innate incapacity. With proper education and training, these groups could become equal members of American society.

This belief led to a "civilizing agenda" whereby the federal government encouraged Native Americans to form compact communities where they would take up settled farming and abandon communal land holding for the benefits of private ownership. The ultimate aim was that whites and Indians would "become one people," in the words of Thomas Jefferson.

One of Guyatt's surprising findings is how many liberals believed that the Indian population should be assimilated through intermarriage. "You will mix with us by marriage," Jefferson told an Indian delegation in 1808. "We shall all be Americans." Not all whites agreed, of course. In the 1820s "all hell broke loose" in Cornwall, Conn., when two young Indian men who arrived to study at a religious school ended up marrying local white women.

Despite the liberals' vision of harmony, conflict reigned on the frontier. After the War of 1812 broke the power of Indian nations east of the Mississippi River, hundreds of thousands of white settlers poured across the Appalachians, eyeing Native American land. Reformers feared the Indians were destined for extinction. The only alternative, they concluded, was for them to be transported far from the white presence. In this interpretation, Andrew Jackson's policy of Indian removal, which produced the infamous Trail of Tears, reflected not so much a hatred of Indians but a desire to ensure their survival.

When it came to African-Americans, the liberals' preferred approach was removal to Africa, a policy known as "colonization." Guyatt is correct to insist that historians have not taken the idea of colonization seriously enough. It was hardly a fringe movement; statesmen from Thomas Jefferson to Henry Clay and, as late as 1862, Abraham Lincoln saw colonization as the only way to end slavery peacefully and with the consent of slaveholders. It also attracted some support among blacks. Most, however, strongly resisted; indeed their opposition to colonization was a crucial catalyst for the emergence of radical abolitionism, which demanded equal rights for blacks within the United States.

Like Indian removal, Guyatt argues, colonization emerged after reformers abandoned the idea that blacks could be assimilated into American society. The first emancipation — gradual abolition in the Northern states — was not coupled with colonization. Reformers assumed that children born to slaves would find a place as free Americans after serving apprenticeships that helped them overcome the "degradation" caused by slavery (not by innate inferiority).

Guyatt makes clear that rather than being fixed, racial attitudes evolve historically. The initial status of free blacks in the new nation was, to say the least, confusing. The Naturalization Act of 1790, which barred nonwhite immigrants from becoming citizens, envisioned a racially exclusive Republic. Yet in the same decade the federal government issued certificates of citizenship to black sailors as well as white to protect them from impressment by the British Navy. Black men could vote in most of the original 13 states. As the 19th century progressed, however, prejudice steadily increased and free blacks' rights were stripped away. And intermarriage was even less of an option than with Indians. The charge that abolitionists were promoting racial "amalgamation" helped to spark anti-black riots, including one in New York City in 1834. With racism becoming more and more intractable, many critics of slavery (Lincoln among them) came to believe that the only way to rid the country of the institution and secure blacks' rights was by separating the races.

Guyatt's juxtaposition of attitudes and policies relating to Indians and blacks yields important insights. But the book is not entirely persuasive. For one thing, its structure seems at odds with its argument. Chapters on Native Americans alternate with those on blacks, creating a disjointed narrative that makes it difficult to find the links between the two stories. Like many writers with a bold thesis, Guyatt is prone to exaggeration. Given the fact that only a few thousand black Americans ended up in Liberia, established in Africa by the American Colonization Society, can we really say that "separate but equal" was a "founding principle of the United States"?

Guyatt may be guilty of taking too seriously the claims by proponents of separation that they were motivated by the best interests of blacks and Indians. As recent studies suggest, colonizationists seemed remarkably indifferent to the fate of those they sent to Africa. Long after it was apparent that emigrants had a better chance of survival if they settled at sites on higher ground, the society continued to deposit them at Monrovia, Liberia's low-lying, malaria-infested capital.

It is difficult to assess Guyatt's claim that those he calls "liberal" invented segregation. Many advocates of racial separation were hardly free from prejudice. Some colonizationists seemed more interested in ridding the country of free blacks than ending slavery or improving the black condition. Indeed, the Colonization Society relentlessly opposed efforts to uplift blacks in this country for fear of making them reluctant to depart. Indian removal owed a great deal not to liberals but to outright racists, including Southern planters who coveted Native American land for the rapidly expanding Cotton Kingdom. Many reformers strongly opposed the policy. Was Andrew Jackson an "enlightened American" when it came to relations with the Indians?

Viewing the story fundamentally as a problem of race relations obscures the crucial difference between the place of Native Americans and blacks in the emerging national economy. The bottom line is this: To fulfill their own aspirations, white Americans needed Indian land and black labor. That is why Indian removal took place but black colonization — apart from a few thousand souls — never did.