|Muir popularized a radically new concept of American land use and conservation. His writings moved presidents, congressmen, and ordinary Americans to action.
President Cleveland's drew on Muir’s work to establish thirteen forest reserves and what became the US Forest Service. Muir was directly involved in establishing Yosemite , Sequoia , Mount Rainier , and Grand Canyon  National Parks. Muir is often called the Father of Our National Park System.
In 1892, he helped found, together with Robert Underwood Johnson, the Sierra Club, to protect the newly created Yosemite National Park and to ... do something for wildness and make the mountains glad... Muir and the Sierra Club fought many battles to protect Yosemite and the Sierra Nevada. He served as the Club's president until his death in 1914.
Muir personally knew three presidents, and many writers and philosophers. He exerted his greatest influence on Theodore Roosevelt. In 1901, Muir published Our National Parks, a book that brought him to President Theodore Roosevelt's attention. In 1903, Roosevelt visited Muir in Yosemite. Together, they laid the foundation of Roosevelt's innovative conservation programs. Soon after that meeting, Roosevelt started on a course of action that established 148 million acres of national forest, 5 national parks and 23 national monuments during his presidency.
When Muir began his conservation career in the late 1880's, America saw its wild lands as reservoirs of commodities needed to drive its industrial engines. When he died in 1914, the Nation was committed in spirit, to the wise use of its natural resources. Today Muir's influence lives on in the public’s appreciation and support of America’s wild places..
He was ...a practical man, a faithful citizen, scientific observers, a writer of enduring power, with vision, poetry, courage in a contest, a heart of gold, and a spirit pure and fine... Robert Underwood Johnson.