5 Historical Conservationists You Should Know

Public Domain. John Muir, 1902. Photo: Library of Congress

How well do you know some of history's most influential environmental activists?

The conservation movement is hardly new. For hundreds of years, people have been advocating for the preservation and protection of the natural world. Some early activists educated the public on the consequences of deforestation. Others exposed humanity's exploitation of natural resources for profit and encouraged the development of national parks. Still others revealed the dangers of chemical pesticides on animals. With activists spanning from 17th century England to 20th century America, here are five of the most important figures in the history of conservation.

1. John Evelyn

John Evelyn

Wikimedia Commons/Public Domain John Evelyn (1620-1706) was an English country gentleman who served on a variety of royal commissions and councils under King Charles II. Evelyn was a fan of gardening, designing his first garden at the age of 22. Over the course of his life, he authored about 30 books, including one of the most influential books on forestry in history: "Sylva, or a Discourse of Forest-trees, and the Propagation of Timber"."Sylva" was the first comprehensive study of trees in the United Kingdom. It was presented as a paper to the Royal Society, a recently founded British national scientific society, in 1662 and published as a book in 1664. The book advocated for the replenishment of England’s forests, as industrialization and a recent Civil War had caused an increase in timber production, greatly depleting the nation’s woods. The book also provided detailed descriptions of the various types of trees in the United Kingdom, explaining how to cultivate them and cataloging their uses. Sylva was a best seller and encouraged wealthy aristocratic landowners to plant trees, eventually replenishing the depleted forests.

Keith Moore, the head librarian of the Royal Society, told BBC News:

Evelyn's work in planting forest trees and harvesting the products from them - whether it was wood or apples - really hit the mark. Of course, you have to remember that this was after the Civil War so trees across the nation had been denuded as part of the war effort but, as Evelyn himself says in the book, as a result of industrial activities - such as glass making - people were chopping down trees, therefore they had to be replaced.

Ten editions of the book were published by 1825, and the text is now available online for free.

2. Henry David Thoreau

Henry David Thoreau

Wikimedia Commons/Public Domain Henry David Thoreau (1817-1862) was an American author and philosopher best known for his 1854 book "Walden; or, Life in the Woods." The book described Thoreau’s experience living alone in the woods for over two years and is considered to be a masterpiece of nature writing.

At the time that the book was published, many of Thoreau’s contemporaries considered him an eccentric, and the book was not well received. Today, however, Walden is the most widely read 19th century non-fiction book and has been translated into numerous languages. The simple living and cooperation with nature that Thoreau described in Walden reflected his advocacy for preserving the wilderness. In his essay Walking, he proclaimed, “In Wildness is the preservation of the World,” arguing that people could not survive without nature. He also advocated for the federal ownership of woods and mountain ranges to protect them from commercial exploitation. The National Wildlife Federation (NWF) inducted Thoreau into their Conservation Hall of Fame in 1967, calling him a “conservation pioneer.”

3. Hugh Cleghorn

Hugh Cleghorn

Wikimedia Commons/Public Domain Hugh Cleghorn (1820-1895) was born in Madras, India to Scottish parents. He was first employed as an assistant surgeon by the East India Company at the Madras General Hospital. Cleghorn soon became fascinated by botany, and after studying plants and trees for several years, he began to give speeches about the failure of agriculture in India, catching the attention of the Indian administration. With the assistance of the administration, he helped establish the Madras Forest Department, today known as the Tamil Nadu Forest Department, India's first forest conservation organization. He was appointed Conservator of Forests in 1856 and Joint Commissioner for Conservancy of Forests later in 1867.

Through his research in botany, Cleghorn realized that the British colonization of India had increased consumption of timber in the region, inevitably causing deforestation. He noted that the construction of new railroads by the British resulted in the consumption of an unsustainable amount of timber. He also exposed the colonizers' cultivation processes as inefficient and dangerous to the environment. His teachings were instrumental in protecting India's forests, and his findings encouraged the government to reform their timber cultivation methods. Among these reforms was the banning of “kumri,” a type of shifting cultivation that Cleghorn described as a “wasteful and barbarous system.”

Today, Cleghorn is known as the “father of scientific forestry in India.” His role in developing a program for forest conservation in the region was vital in protecting India’s natural resources from exploitation.

4. John Muir


GOGA Park Archives/Flickr/CC BY 2.0 John Muir (1838-1914) is debatably the most influential naturalist in American history. Often referred to as the “Father of Our National Park System,” Muir was an advocate for the protection and preservation of significant nature areas. He wrote articles about conservation for numerous magazines including The Century, in which he exposed the destruction of forests and meadows in the mountains. His writings influenced congress to create a number of national parks including Yosemite, Petrified Forest, Grand Canyon, Mount Rainier, and Sequoia.

Robert Underwood Johnson, an editor for The Century that had aided Muir in some of his environmental campaigns, suggested that he start an organization to protect the Sierra Nevada from degradation. In 1892, Muir founded the Sierra Club with a group of his supporters. The Club aimed to establish new national parks and to convince the government to better protect Yosemite. Today, the Sierra Club is the largest grassroots environmental organization in the world with over 2.4 million members.

Muir is also famous for his three-night camping trip with President Theodore Roosevelt in Yosemite in 1903. After reading Muir’s 1901 book, "Our National Parks", Roosevelt decided to visit Muir in Yosemite, stating, “I want to drop politics absolutely for four days and just be out in the open with you.” During the trip, Muir convinced the president to expand the federal protection of the land in and around Yosemite National Park after exposing him to the exploitation of the valley’s resources and the degradation of the land. The trip forever shaped Roosevelt, who used what Muir taught him to improve his conservation programs.

5. Rachel Carson

Rachel Carson

U.S. Department of Agriculture/CC BY 2.0 Rachel Carson (1907-1964) was an American marine biologist and writer best known for her 1962 book, "Silent Spring," which exposed the dangers of chemical pesticides, especially DDT. In her book, Carson argued that pesticide use posed a serious threat to the livelihood of fish and birds and could have hazardous effects on children. Her work encouraged the United States government to ban DDT, and Silent Spring is often regarded as a catalyst for the modern environmental movement and the development of the U.S. Environmental Protection Agency.

Before writing "Silent Spring," Carson worked for the U.S. Bureau of Fisheries, later renamed the Fish and Wildlife Service, eventually becoming the Editor-In-Chief of all of their publications in 1949. She also wrote numerous articles on marine biology for newspapers and magazines and published three books about the ocean, "Under the Sea-Wind," "The Sea Around Us," and "The Edge of the Sea.". Carson’s publications taught the public about the natural world, and many of them highlighted the ability of humans to alter nature. However, it was not until Carson became fascinated with the increased use of synthetic pesticides after World War II and published "Silent Spring" that she solidified her legacy as one of the most influential conservationists of all time.

Biographer Linda Lear perfectly summed up Carson’s legacy in her 1997 biography, Rachel Carson: Witness for Nature:

Her courage in sounding the alarm and her ecological vision of the oneness of all life indelibly shaped the contemporary environmental movement and anticipated the global crisis we face in the 21st century.

Updated April 21, 2020