John Muir was a naturalist, conservationist, explorer, and writer. At age 11, his family immigrated to the United States from Scotland and settled in Wisconsin. Muir learned to love the wilderness at an early age and even carved working locks out of wood. At age 21, he entered the University of Wisconsin, but left after three years. After suffering an eye injury while working in Indiana, Muir resolved to work in the wilderness.

In 1868, after roaming the North American continent, Muir landed in San Francisco. Muir explored California and was awestruck by its natural beauty. He soon became a successful writer, describing the landscapes and detailing the devastation of alpine meadows and forests by grazing sheep and cattle. As a result of his efforts, Congress established Yosemite National Park in 1890. Muir was also involved in the creations of Sequoia, Mount Rainier and Petrified Forest National Parks. To protect the parks from poachers and land prospectors, Muir, and his supporters, formed the Sierra Club in 1892. He served as its president until his death in 1914.