Something about land lies deep in the American psyche. Since the early 20th century most Americans have resided in cities and suburbs, yet the mystique of agrarian life draws millions to farmers’ markets and makes the family farm a touchstone of American politics. The cowboy, that rugged knight of the open West, remains an icon of American culture. Squabbles between developers and preservationists over land use become battles over the meaning and destiny of America.

That’s because they are battles over the meaning and destiny of America. The history of America’s land is the history of the country itself. America grew into its defining institutions even as it grew into its land. The land inspired American independence; it spawned American democracy; it undergirded America’s rise to world power. Land symbolized opportunity to generations of Americans, starting with colonists who never had the chance of owning property in Europe; the vast continent gleamed in their eyes and its frontier drew them west. When the open spaces filled up, Americans suffered an identity crisis: Without the frontier of open land, who would we be?

George Washington knew the frontier well as it existed in 1763. He had surveyed lands of the Ohio Valley, then deep in Indian territory, and he had led a Virginia regiment in the French and Indian War, fought primarily on the frontier. At the war’s end, he expected to capitalize on his knowledge of the frontier by gaining legal title to thousands of acres in the West, which he would hold for resale at a higher value.

But then the British imperial government issued a proclamation declaring all territory west of the Appalachian mountains closed to settlement. The war had thrown Britain deeply in debt, and cost-cutting was imperative. Western settlement would cause further friction with the Indians, necessitating new spending on frontier defense. London couldn’t afford the latter, so it wouldn’t allow the former. The West was closed.

Washington already bristled under British rule. Though a gifted soldier, his colonial origins limited his advancement in the British army. This personal slight was suddenly compounded by the proclamation’s blow to his business plans. He had spent a great deal of effort—and no small amount of money—on his Ohio project; he had risked his neck and lost good men securing the West to Britain. Now the British government was keeping him from his hard-earned prize. And there was nothing he could do, for as a colonial he had no representation in Parliament.

Washington wasn’t a philosopher like fellow Virginian Thomas Jefferson. Where Jefferson thought in terms of natural rights, Washington, a practical man, dealt in material things like land. The British government was depriving him of land—land he had fought for and fairly won. It was enough to make him reconsider his allegiance.

Before long, a critical mass of Americans joined Washington in concluding they needed a government of their own. Complaints over taxation and other issues joined the land question in triggering the American Revolution, which ended with the Americans in possession of the Ohio Valley and much more.

The new land proved the British right about one thing: More western settlement meant more trouble with the Indians. To the tribes of the Ohio and Mississippi valleys, American independence was a disaster. The Americans were more aggressive in seizing land than the British had been. Often tribes secured treaties from the governments of the white settlers, but those treaties rarely inhibited the whites from taking what land they wanted.

At times the Indians resisted. In the first years of George Washington’s presidency, an Indian confederacy that formed in the region between the Ohio River and the Great Lakes inflicted a series of defeats upon settlers and local militia groups. They received arms and moral support from the British, who, still stinging from the loss of their 13 American colonies, were happy to provoke trouble for the upstart republic.

Washington summoned one of his lieutenants from the Revolutionary War, Anthony Wayne, known as Mad Anthony for his impetuous style of command. Wayne led America’s first federal army under the Constitution, called the Legion of the United States, against the Indian confederacy and won a decisive victory at the Battle of Fallen Timbers, near modern Toledo.

The victory allowed the settlement of Ohio, but it meanwhile foreshadowed a century of struggle between whites and Indians over land along the westward-moving frontier.

In the 18th century Benjamin Franklin calculated that the American population doubled every 20 years. For an agricultural people, as Americans overwhelmingly were at the time, this had an obvious corollary: American territory needed to expand lest the country become crowded and the people impoverished. Americans looked at Europe, already crowded, and determined not to become like that.

Thomas Jefferson admired Franklin and read his calculations. And when Jefferson, elected president in 1800, had an opportunity to double America’s domain by purchasing the western half of the Mississippi Valley—the region called Louisiana—he seized it.

The purchase cost Jefferson some sleep. Long an advocate of interpreting the Constitution narrowly, Jefferson scanned his copy of the document and saw nothing permitting Congress or the president to purchase new land. Had he been true to his constitutional principles, he should have told Napoleon, the French leader who offered Louisiana for sale, thanks but no thanks.

But another of Jefferson’s principles told him to take the deal. Jefferson was the first president to call himself a democrat—30 years before his party would call themselves Democrats—and he believed that the success of America’s experiment in self-government depended on the virtue and prosperity of the nation’s ordinary people. Jefferson felt obliged to ensure that America’s farmers and their children and their children’s children would have adequate land for their farms.

So he swallowed his constitutional scruples and concluded real estate bargain of the century, or any century. For $15 million (equivalent to perhaps $300 million today) he bought the huge swath of territory between the Mississippi River and the Rocky Mountains.

While Jefferson the democrat was adding land to America, access to land had a democratizing effect on American life. The noble classes in Europe exercised dominance on account of their land; serfs and peasants labored on the nobles’ land. The limited supply of land let this closed system persist. In America, by contrast, the abundance of land made property cheap. Far greater numbers of people could acquire land of their own. These independent farmers formed the backbone of the American republic.

And their political power grew over time. In the first years of the republic, property and residence requirements kept all but a small minority of citizens from voting. But during the next generation, the electorate expanded. New states established in the West enticed settlers with the promise of full political equality—that is, voting rights not dependent on wealth or long residence. A competition developed among states, each eager to lure more new residents. In self-defense, the old states of the East lowered their qualifications. By the time Andrew Jackson was elected president in 1828, nearly all adult white males could vote.

Long before Americans filled up the land they had already acquired, they were demanding more. They hungered for Texas in the Southwest and Oregon in the Northwest. James Polk won the presidency in 1844 on a platform of taking both.

Polk was as practical as George Washington, letting his actions speak for him. But some of his supporters provided a theoretical justification for American expansion, presenting it as generous sharing of American values and institutions. In the salad days of democracy, many Americans credibly considered themselves the best-governed people on earth, and it wasn’t ludicrous for them to argue that others would gain from being brought under democracy’s sway.

It was self-serving, though, especially when Manifest Destiny, as the doctrine was called, was used to rationalize a war that delivered half of Mexico to the United States. Some of the Manifest Destinarians were embarrassed by the patent aggression of the conflict, but even they gaped in wonder when gold was discovered in California. Providence, it seemed, was rewarding America for its audacity.

Enthusiasts of Manifest Destiny envisioned a continental future for the United States, in which the Stars and Stripes would wave from Arctic Ocean to the Isthmus of Panama. Already the country had spanned North America from east to west; why not from north to south?

Part of why not was the divisiveness of slavery, which disposed Southerners to distrust northerly expansion, and Northerners to distrust southerly expansion. Part was an implicit contradiction in Manifest Destiny itself. If the point was to spread popular government, what happened when the people over which it was to be spread objected to the spreading, as Canadians and Mexicans emphatically did?

Yet the larger reason was the transformation of the American economy. More land was crucial to a growing population of farmers. But it meant far less to urban workers, who formed an increasing part of the American electorate. After a final fling with Alaska, purchased from Russia in 1867, American expansion clanged to a halt amid the roar of the Industrial Revolution.

Even so, the enormous domain America already controlled enabled its industrializing economy to become the envy of the earth. American mines spewed iron, coal, copper and other raw materials essential to modern industry. American wells gushed oil that became the lubricant and fuel of modern life. American rivers and harbors sustained shipping that carried American products across the globe. By the end of the 19th century, America led the world in manufacturing.

The conversion of that prowess to world leadership was simply a matter of time.

Yet when the census of 1890 revealed that the American frontier had disappeared—that there was no line separating the settled regions from the unsettled—much of the country fell into a funk. For almost 300 years the American identity had been inseparable from the opportunity provided by an abundance of land. The process of settling the land, of taming the frontier, had made America a magnet to millions of immigrants, an engine of economic growth, a beacon of liberty, a model of political and social equality.

Now that opportunity was gone, or at least greatly diminished. America’s borders were fixed; suddenly the country looked alarmingly like the Europe which Americans had long derided.

Yet for all the hand-wringing, the American future didn’t end when the land ran out. In fact, the land didn’t run out, as anyone flying across the continent in the 21st century can tell. Especially in the West, there remain huge spaces hardly touched by human habitation.

By now far more people live in cities than on the land. Yet those centuries of obsession with land still echo. John Kennedy, the first president born in the 20th century, proclaimed a “new frontier” for his administration. The sustained popularity of the television series Star Trek and its Hollywood spin-offs had much to do with its characterizing of space as the “final frontier.” Elon Musk and other visionary entrepreneurs today are making big bets on this latest frontier.

Something about the land, and the frontier, remains embedded in America’s psyche. By now it might be mostly memory—but memories can be powerful.

H. W. Brands holds the Jack S. Blanton Sr. Chair in History at the University of Texas at Austin. A New York Times bestselling author of more than 30 books, he was a finalist for the Pulitzer Prize in biography for The First American and Traitor to His Class.

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