In April 1805, Meriwether Lewis and William Clark and their pirogues wended up the Missouri River just past the Yellowstone into what now is Montana. It was wild, open country under a big sky—and most of it still is. To celebrate July 4, 1976, the late historian Stephen Ambrose took his family to Lemhi Pass at the other end of Montana, nearly 500 miles west, where Lewis was the first American to cross the Continental Divide. Ambrose noted that the terrain was little changed from when Lewis and Clark passed through. In recent years, many have come to Montana, to see for themselves this vast land—buying up ranchlands or condominiums, or campaigning politically, as Barack Obama did on July 4, 2008.

Yet American civilization has only lightly encroached on Montana. It is still a land of great empty vistas, with mountains in the west and vast expanses of plateaus and plains in the east—the 4th largest state in area and 44th in population. Almost nowhere in the state is the wilderness out of sight; it has the Lower 48’s largest population of grizzly bears and buffalo. Montana sits atop the continental United States, spanning the Rockies so that on Interstate 15 one can cross the Continental Divide three times. Lewis and Clark found those mountains a fierce barrier, and Montana has not been much of a crossroads. The first Americans here were itinerant trappers seeking fur and miners seeking gold, silver and copper. They built ramshackle towns and in a few cases gained sudden wealth, which made them kings not of their barren homestead but of the metropolises back east. Then came the workers who built and serviced the Northern Pacific and Great Northern railroads, followed by wheat farmers and ranchers.

Statehood arrived in 1889, less than a century after Lewis and Clark. The mining economy gave Montana a radical, class-warfare political tradition. On one side was the Anaconda Mining Company, which until 1959 owned five of Montana’s six daily newspapers, the Montana Power Company and many of its politicians. It had strong allies in the Stockmen’s Association and the Farm Bureau. On the other side were progressives like Sen. Thomas Walsh, who exposed the Teapot Dome scandal, and Sen. Burton Wheeler, a New Dealer who broke with Franklin D. Roosevelt over court packing and isolationism. Allied with them were the labor unions (Montana has no right-to-work law and has been the most pro-union Rocky Mountain state), and pork barrel beneficiaries (for a while in the 1930s, Montana received more federal money per capita than almost any other state). The focus of all this was Butte, with its gold and copper mines on ‘‘The Richest Hill on Earth,’’ with its gamblers, bootleggers, and millionaires, its company goons and union thugs, IWW organizers and its Socialist mayor. Today, Butte is far smaller. The mines are closed, the ore depleted, and the stone temples of commerce are grim; looming mine heads are being restored to a cleanliness they never enjoyed in the boom days.

Butte’s population peaked in 1920, mines gradually closed all over the state, and agriculture—wheat growing and cattle grazing—became the mainstays of the economy. Class warfare died down. Other towns grew, though only Billings has topped 100,000. Others growth areas were the university town of Missoula, Great Falls just east of the Rockies, Kalispell near Flathead Lake, the university and resort town of Bozeman, and the state capital of Helena. The muscular tone of a land settled by ranch hands, miners and railroad workers, by men who do hard physical work and relax hard afterward, remains a link with Montanans going back to the mountain men, miners and cowboys who drove herds of Texas longhorns across the open range. And there is still the sense of space. Hunting and fishing opportunities abound; development in the small cities and resort areas has not been enough to drive the game away.

Over the past quarter-century, the Big Sky country attracted at first a trickle and then a flood of affluent Americans who purchased second homes here—high-visibility movie stars and billionaires like Ted Turner, but also just ordinary people buying small spreads near Big Sky or McLeod, near Bozeman, or around Flathead Lake or Big Timber or the Big Mountain ski resort in Whitefish. Many newcomers, from California and other urban states, are setting down roots here, as computers, modems and fax machines make it possible for small businessmen and entrepreneurs to work in Montana, far from their customers and clients but in an environment they love—and not far from the coffee houses and gambling parlors one finds along every highway. These new Montanans have added a spark of energy and inventiveness to a population that had consisted of those left behind when others moved elsewhere. Montana grew 13% in the 1990s and another 7% between 2000 and 2008, despite losses in the eastern plains. New Census Bureau estimates put total population at 967,440. The state’s economy, fueled by construction and strong agricultural commodity and energy prices, continued to grow during the 2001 recession and after, and unemployment reached a historic low of 2.8% in 2007. Growth was especially vigorous around Bozeman and Big Sky, in Missoula and Ravalli County to the south, and around Kalispell and Lake Flathead to the north, while most of the eastern plains counties have lost population.

Sometimes newcomers are startled by the hardness of Montana life. The DeLorme Montana Road Atlas gives advice on what to do if you should encounter a bear. There are lively political arguments over the grizzly bears and gray wolves reintroduced to Montana in the 1990s. The American Prairie Foundation, funded by Manhattan and Silicon Valley millionaires, is buying up land in the northern plains to create a reserve where buffalo and prairie dogs can roam and to attract tourists and hunters. The Nature Conservancy has been persuading ranchers in Phillips County to change their practices. The state conducted a lottery in 2006 for 50 licenses (Indian tribes were allotted 16 of them) to hunt buffalo north and west of Yellowstone National Park because ranchers fear that the buffalo will transmit brucellosis, which causes cows to abort, to their herds.

Montana has had two lively political traditions. One draws on its heritage of class-warfare politics, radical miners and angry labor unions, which made Montana for many years the most Democratic of the Rocky Mountain states. From 1952 to 1984, it elected only Democrats to the U.S. Senate, and since 2006, it has two Democratic senators again. The other, more recent tradition is in line with conservative activist Grover Norquist’s “Leave-Us-Alone-Coalition”—a fierce opposition to higher taxes and federal government dictates. Montana has not elected a Democrat to the U.S. House since 1994, and Montana gave George W. Bush big majorities in 2000 and 2004. Barack Obama’s campaigning and organization in 2008 held John McCain to a narrow plurality win. The Democratic tradition is strongest in the old mining towns like Butte and Anaconda, on Indian reservations (7% of Montanans are Indians), in old railroad towns like Great Falls and Havre, in university towns like Missoula and Bozeman, and in the state capital of Helena. The Republican tradition is strongest in the population-losing eastern plains counties and in fast-growing Flathead and Ravalli Counties in the west.

In recent years the Democratic tradition has mostly prevailed. Republican Dennis Rehberg, the state’s lone U.S. representative, has continued to win House elections by wide margins, but Democrats have won by similarly impressive margins in other races. Rancher Brian Schweitzer, after running a strong race for senator in 2000, was elected governor by 50%-46% in 2004 and was rousingly re-elected, 65%-33%, in 2008. For several years, the Legislature has been closely divided between the two parties. In 2006, Democratic state Sen. Jon Tester edged out, 49%-48%, three-term U.S. Sen. Conrad Burns, who had received more contributions from Indian tribe clients of disgraced lobbyist Jack Abramoff than any other member of Congress. This was a key race in giving Democrats a majority in the Senate. And in 2008, Democratic Sen. Max Baucus, thought to be in trouble going into the 2002 cycle, was re-elected to his sixth term, 73%-27%, the biggest percentage victory in Montana since Democratic Sen. Mike Mansfield won 76%-24% in 1958, over a nuisance candidate. Baucus, as chairman of the Senate Finance Committee, wields more clout on Capitol Hill than any Montanan since Mansfield, who was the Senate majority leader, retiring in 1976.