By the end of the nineteenth century, the West was effectively settled. Railroads stretched across all parts of the region, from the Great Northern, which ran along the Canadian border, to the Southern Pacific that ran across Texas and the Arizona and New Mexico territories to link New Orleans and Los Angeles. The influx of homesteaders, ranchers, and miners swelled the census rolls and led to the admission of Nevada (1864), Colorado (1876), South Dakota, North Dakota, Montana, Washington (all four in 1889), and Idaho and Wyoming (1890) to the Union. New towns and cities created by the cattle or mining boom, such as Abilene, Denver, and San Francisco, dotted the trans‐Mississippi West.
The Oklahoma Land Rush. Under President Andrew Jackson, Native American tribes from the Southeast had been resettled in what became Oklahoma. Long considered remote and unproductive, the land became increasingly valuable and, by the 1880s, the federal government was under pressure to open it to non‐natives for settlement. Congress responded by putting two million acres of the Indian Territory into the public domain. At noon on April 22, 1889, more than 50,000 men, women, and children (popularly known as the Boomers) on horseback, in wagons, and even on bicycles stampeded into what is now central Oklahoma to stake out their claims. Within a few hectic hours, all the available land was settled, with the choicest acreage actually going to the Sooners, those who had crossed the line before the official beginning of the land rush. An additional six million acres in the Oklahoma Panhandle called the Cherokee Strip was opened for settlers in 1893.
Frederick Jackson Turner and the frontier. A year after the Oklahoma Land Rush, the director of the U.S. Census Bureau announced that the frontier was closed. The 1890 census had shown that a frontier line, a point beyond which the population density was less than two persons per square mile, no longer existed. The announcement impressed Frederick Jackson Turner, a young historian at the University of Wisconsin. In 1893, he presented a paper to the American Historical Association entitled “The Significance of the Frontier in American History.” In it he argued that the experience of the frontier was what distinguished the United States from Europe; the frontier had shaped American history as well as produced the practicality, energy, and individualism of the American character. Turner's claims about the effects of the frontier on American life influenced generations of historians, particularly in their appreciation of the role of geography and the environment in helping to shape national development.
With more people homesteading farms after 1890 than in the decades before, the Western experience was far from over. But with the approach of the new century, there was a new appreciation of the environment and the scenic values of the West. As the frontier officially disappeared, popular interest in preserving wilderness grew. Although Yellowstone National Park in Wyoming was established in 1872, California's Yosemite (1890) was the first national park specifically designed to protect a wilderness area. In 1891, Congress passed the Forest Reserve Act authorizing the president to close timber areas to settlement and create national forests by withdrawing the land from the public domain. President Benjamin Harrison immediately set aside 13 million acres under the legislation. Naturalist John Muir, who was a driving force behind the creation of Yosemite, founded the Sierra Club in 1892 to protect the Pacific Coast's mountain ranges. For all the preservation sentiment, there were also trends developing that emphasized more fully utilizing the resources of the West. The twentieth century's large‐scale irrigation projects, dams, aqueducts, and power lines that would bring water and electricity hundreds of miles to the region's major cities would transform the West in ways that could not be imagined in 1890.