Environmentalism

THE LATE 19th and early 20th centuries witnessed growing concern in the United States over the fate of pristine wilderness areas, particularly in western states, as well as the need for conservation of such areas throughout the country. In 1854, Henry David Thoreau's Walden advocated a return to a more simple and natural existence. John Muir's travels and writings in the late 19th century were instrumental in setting aside large areas of land for preservation, most notably Yosemite National Park. Muir was also a cofounder of the Sierra Club.

Others, such as Gifford Pinchot, appalled at the rapid exploitation of resources, advocated the need for conservation through the “wise-use” and management of wilderness areas. By the beginning of the 20th century, the concerns of conservationists and ...