John Muir (1838-1914) was a Scottish-born American naturalist, writer, and advocate of U.S. forest conservation. As early as 1876 Muir urged the federal government to adopt a forest conservation policy. In 1890, due in large part to Muir's efforts, an act of Congress created Yosemite National Park. In 1892 Muir and a number of his supporters founded the Sierra Club, an organization devoted to protecting the environment. He served as its first president, a position he held until his death in 1914. Muir's personal involvement was instrumental in the establishment of many of the country's other national parks: Sequoia National Park, the Petrified Forest, Muir Woods National Monument, and Grand Canyon National Park.

John Muir died in Los Angeles on December 24, 1914, of pneumonia at the age of seventy-six. His writings continue to serve as sources of inspiration for naturalists and conservationists the world over and remain important works in the body of literature on America's natural history.