Theodore Roosevelt is known as the “conservation president” for his undaunted efforts, at the dawn of the 20th century, to shield wildlife and public lands from development. His efforts helped establish America’s national park and forestry services, putting more than 200 million acres of land under public protection. But transferring all that territory to government control came at a steep cost to Indigenous people, who had been stewarding those lands for generations.

A Harvard-educated New Yorker, Roosevelt was deeply inspired by nature and the mythos of the western frontier. A lifelong hunter and explorer, he continually ventured into the wilderness for renewal—from the backwoods of Maine to the Dakota Badlands to an unmapped river in the wilds of Brazil. In his youth and early adulthood, he often pursued “the strenuous life” to help ameliorate physical ailments, build character and overcome deep personal losses. Later, his relationship to nature took on an almost spiritual quality.

As president, Roosevelt cultivated friendships with conservationists like John Muir and Gifford Pinchot, who inspired him to transform his reverence for nature into national policy. “The nation behaves well if it treats the natural resources as assets which it must turn over to the next generation increased,” he said in a speech in Kansas in August 1910_._

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Throughout his life, Roosevelt sought knowledge, respite and adventure in the natural world. Beset by childhood illnesses, young “Teedie” was a lover of adventure books who became a passionate student of nature. By 12, he had collected hundreds of birds and animal specimens for his self-named “Roosevelt Museum of Natural History.” By his late teens, he was a keen woodsman, hunter and taxidermist.

Rugged landscapes gave him refuge in times of tragedy. After losing his father, a 19-year-old Roosevelt tested his mettle with an arduous expedition into the remote Maine woods. In 1884, gutted by the tragic deaths of his young wife and mother on the same day, he escaped to what he called the “savage desolation” of the North Dakota Badlands, where he spent several years struggling as a cattle rancher.

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As president, Roosevelt was guided on a through Yosemite National Park by naturalist John Muir for three days in 1903. After viewing Mariposa Grove, Sentinel Dome, Glacier Point and other sights, he seemed to have a spiritual epiphany. In his autobiography, he wrote of camping among the sequoias: **“**The majestic trunks, beautiful in color and in symmetry, rose round us like the pillars of a mightier cathedral than ever was conceived even by the fervor of the Middle Ages.”

Roosevelt, who had seen firsthand the grave impact of overhunting the bison and overgrazing frontier ranch lands, knew America’s natural resources weren’t infinite. As president, he pressed an ambitious conservation agenda. He set aside 150 national forests, 51 federal bird preserves, four national game preserves and five national parks. In addition to establishing the National Forest Service in 1905, he also established 18 national monuments under the Antiquities Act of 1906—including the Grand Canyon, which later became a national park. All told, Roosevelt was responsible for protecting about 230 million acres of public land and setting in motion the establishment of the National Park Service in 1916, which has been described as “America’s best idea.”

Throughout the 19th century, Native peoples had been gradually pushed out of their ancestral lands through treaties and violent removal tactics. The establishment of national parks and forest lands—a process begun several decades before Roosevelt’s time, but greatly accelerated by his administration—dealt yet another blow to Indigenous peoples who had lived and thrived in those areas for hundreds of years, often side by side. Chaco Culture National Historical Park in New Mexico, first set aside by Roosevelt in 1907 by federal decree, is claimed as significant by 39 federally recognized tribes. They, like scores of tribes around the country, knew these areas as sacred, beautiful and awe-inspiring.

Roosevelt continued his predecessors’ push to remove Native Americans from their ancestral territories. According to environmental historian Theodore Catton, some 86 million acres of tribal land transferred to the national forest system, much of it during Roosevelt's tenure. America’s 423 national parks, meanwhile, comprise about 85 million acres—also once largely the province of Native peoples. “The rise of conservation dovetailed with a national closeout sale on the Indians’ landed heritage,” wrote Catton.

This legacy reflected a fundamental clash of world views. “These areas were intimately known by the Indigenous people who traveled through and used these areas,” Tabitha Erdey, cultural resources program manager for the Nez Perce National Historical Park, told HISTORY.com. By contrast, “Euro-Americans saw these areas as wilderness, as empty spaces that were in need of civilization and control.”

Roosevelt’s Indian removal policies also reflected his own racial biases. In 1886, he said, “I don’t go so far as to think that the only good Indian is the dead Indian. But I believe nine out of every ten are, and I shouldn’t like to inquire too closely into the case of the tenth.”

Advisors like Muir held similar disdain. In his 1894 book-length tribute to the Sierras, “The Mountains of California,” Muir called the wilderness “a manuscript written by the hand of Nature alone”—ignoring the fact that Miwok Indians had long cultivated the Yosemite Valley with intentional fires, trimming and tending of mighty oak trees for acorns. And while Muir’s text extensively detailed the area's flora and fauna, he made no mention of its Native inhabitants, except when he encountered a group of Mono Indians on a pass. He described them as “mostly ugly, and some of them altogether hideous… Somehow they seemed to have no right place in the landscape, and I was glad to see them fading out of sight down the pass.”

For Indigenous people, who had stewarded these wilderness areas since long before Euro-American immigration, the park designations meant further loss of homes, food sources and sacred sites.

Glacier National Park was established on lands once home to the Blackfeet, who called this part of the northern Rockies “the backbone of the world.” As with many national parks, sacred tribal sites quietly pepper the landscape. By the late 19th century, the Blackfeet faced starvation after being restricted to a reservation. Desperate and with few options, they sold 800,000 acres of the reservation to the government, with a stipulation that they would be able to hunt there.

Chief White Calf of Blackfeet decried the loss of sacred areas, calling it his people’s “last refuge.” Another chief, Little Dog, wrote a letter to the secretary of the interior in 1895, stating the Blackfeet “did not ask the government to come and buy their land.” The ceded land became a forest reserve in 1897 and became a part of Glacier National Park when it was founded in 1910, further restricting the Blackfeet from traditional use in the area.

The Oglala Sioux spiritual leader Black Elk in 1929 expressed his anger at how Americans had “made little islands for us and other little islands for the four-leggeds, and always these islands are becoming smaller.” He decried the displacement of Native people from the Badlands National Monument near his home on the Pine Ridge Reservation, and also from the nearby Black Hills.

Black Elk recalled a time in his youth when both animals and human beings “lived together like relatives, and there was plenty for them and us."