From pioneers of environmentalism to modern-day activists and campaigners, the world has seen many influential environmental movers and shakers who have dedicated their lives to sustainable development and the preservation of nature. Through their work and legacies these outstanding environmentalists have raised the level of environmental consciousness, inspiring millions of people throughout the world to play an active role in stewardship of the environment.

Rachel Carson (1907 – 1964)

Few have left as great a legacy as Rachel Carson, who paved the way for modern environmentalism. Often credited as “the founder of the environmental movement,” Rachel Carson was passionate about the conservation of natural resources, and through her work she had a significant influence on the modern environmentalist movement.

From an early age, Pennsylvania-born Carson had a love of nature that was fertile ground for a career that would alter the course of conservation. She wrote several articles and books on the marvels of nature in her early career as a marine biologist and as editor-in-chief for the US Fish and Wildlife Service publications. Her work expressed the view that “human beings were but one part of nature distinguished primarily by their power to alter it, in some cases irreversibly.”

In 1962, Rachel Carson published a book that documented the hazardous effects of pesticide.  This book, “Silent Spring,” had momentous consequences for the chemical industry.  It challenged the excessive use of chemicals, eventually leading to the ban of the pesticide DDT. The book was met with strong opposition, but Rachel Carson remained unwavering in her belief that new policies should be created to protect the health of our environment and consequently that of mankind.

In his introduction to the reissue of “Silent Spring,” former vice-president and active environmentalist Al Gore says: “Silent Spring planted the seeds of a new activism that has grown into one of the great popular forces of all time. When Rachel Carson died, in the spring of 1964, it was becoming clear that her voice would never be silenced. She had awakened not only our nation but the world.”

John Muir (1838 – 1914)

A pioneer of conservation, John Muir is renowned as the founder of The Sierra Club. “The Club is America's oldest, largest and most influential grassroots environmental organization.”

Called “the Father of National Parks”, John Muir was born in Scotland but immigrated to the United States at the age of 11, where he was to become one of the most important figures in Californian history. Inspired by the teachings of environmentalist Ralph Waldo Emerson, Muir devoted his life to the protection of wilderness, particularly in the Sierra Mountains, where he felt most at home. Muir’s life was one of adventure and passion. His approach to living is summed up in The Sierra Club motto: Explore, Enjoy and Protect the Planet.

Muir wrote many essays and books on ecology and on the protection of natural resources, and he was outspoken about his belief that “humans are a part of nature and dependent upon it, and that our ability to alter and destroy nature imposes on us an obligation to protect it.”

During his lifetime John Muir achieved widespread recognition for his conservation work. He used his influence to introduce bills to Congress that contributed to the creation of several national parks including Yosemite, Sequoia, Grand Canyon and Mount Rainier. His work also inspired the conservation programs of President Theodore Roosevelt, and via the Sierra Club the legacy of John Muir continues to inspire and encourage environmental campaigners around the world.  Through his efforts he has easily earned recognition as one of history’s most influential environmentalists.

Henry David Thoreau (1817 – 1862)

Henry David Thoreau was an American naturalist who studied the relationship between nature and man. His friend and mentor Ralph Waldo Emerson had a great influence on Thoreau. Emerson encouraged Thoreau to write down his thoughts, and at Emerson’s urging Thoreau began writing a journal in 1837.

Although he wrote many poems and essays, Henry David Thoreau’s most significant work was “Walden” (or “Life in the Woods”), a memoir of his two years of simple living at Walden Pond. Thoreau used the time to contemplate his life by experiencing the simplicity and splendor of nature. As a transcendentalist, Henry David Thoreau believed that nature and God were linked. This view, that there was a direct connection between the soul and the natural world, was reflected in his work. In “Walden,” Thoreau writes: "I went to the woods because I wished to live deliberately, to front only the essential facts of life, and see if I could not learn what it had to teach, and not, when I came to die, discover that I had not lived."

“Walden” demonstrated that humans could live in harmony and tranquility with the environment. The book supports the view that people should live close to nature and dedicate themselves to the preservation and stewardship of the environment. In “Walden” Thoreau wrote: “In wildness is the preservation of the world”.

During his lifetime, Henry David Thoreau was highly criticized for his philosophies and was labeled by some as a cranky hermit in the wild. His work was largely ignored publication after his death in 1862. His writings, including “Walden,” and his journal, which was published after his death, had widespread influence. His writing is studied at schools and universities across the world, making him America’s most notable nature writer.

Although often misunderstood, Henry David Thoreau was able to change the way society viewed man’s relationship with nature. His writings on wilderness preservation have given him the reputation of a true environmental visionary. 

Wangari Maathai (1940 – present)

Wangari Maathai is an environmentalist, activist, writer and politician who made history by being the first African woman to win a Nobel Peace prize in 2004 for “her contribution to sustainable development, democracy and peace.”

Maathai was born in Ihithe village in Nyeri, Kenya. Surrounded by nature, Wangari Maathai’s upbringing paved the way for her passion for conservation. She became the first woman in East and Central Africa to obtain a doctoral degree in 1971. During her involvement with the National Council of Women of Kenya, she initiated tree-planting projects to conserve the environment.

Her enthusiasm for nature and the environment resulted in the founding of the Green Belt Movement in 1977. This environmental non-governmental organization (NGO) is dedicated to increasing environmental awareness and empowering local communities to make a difference. Through campaigning, educating and empowering, the Green Belt Movement has overseen the planting of over 30 million trees. The end result of these tree-planting projects is the “protection and restoration of habitats for local biodiversity.” Consequently, Wangari Maathai has become affectionately known as “the tree lady.”

Not afraid to speak out about her belief that man has a responsibility to protect the environment, Maathai has been influential in the Kenyan government’s stance on the environment and conservation. From 2003 to 2005 Wangari Maathai held the position of Assistant Minister for Environment, Natural Resources and Wildlife, and has actively campaigned for better stewardship of natural resources.

Wangari Maathai has received enormous recognition for her efforts, including the Nobel Peace Prize in 2004 and the Légion d'honneur in 2006.

Maathai continues to inspire people through her work, including her books “Unbowed: A Memoir” and “The Canopy of Hope: My Life Campaigning for Africa, Women and the Environment.”

Al Gore (1948 - present)

Al Gore is one of the best-known environmentalists of the modern day. The former vice-president of the United States of America has used his influence and celebrity to increase environmental awareness, particularly on issues surrounding global warming, becoming the contemporary face of climate change activism.

His fascination with the environment began when he attended a course at Harvard University that tackled the topic of global warming. Subsequently during his political career Gore wrote “Earth in Balance.” Published in 1992, the book focuses on ecological problems and how policy-makers can deal with issues such as climate change and global warming. The book became the basis for the 2006 movie “An Inconvenient Truth,” which is narrated by Gore. The Academy Award-winning movie chronicles the lifework of Al Gore and his efforts to educate the public on climate change and global warming. The stark reality of global warming presented in the film has drawn both widespread praise and criticism. He has been labeled both an environmental hero and a politically motivated individual who has only succeeded in creating hype around the topic of climate change.

Al Gore has tirelessly campaigned for a carbon-neutral society and supports the Tokyo Protocol, which calls for a reduction in the emission of greenhouse gases. He regularly speaks at public events, conferences and universities. Since his political career came to an end, Al Gore has committed himself to educating the public about the harmful effect that carbon dioxide and other emissions have on the environment. In spite of the criticism leveled at Al Gore, he has steadfastly maintained that the world is facing a crisis and that taking action to stop the progress of global warming in its tracks is not optional, but rather essential.

Norwegian Parliament Member Boerge Brende said of Gore: “Al Gore, like no other, has put climate change on the agenda. Gore uses his position to get politicians to understand…I think climate change is the biggest challenge we face in this century.” His fervor for the topic of global warming has led to numerous environmental awards including Spain’s Prince of Asturias award for international co-operation (awarded specifically for his documentary), as well as 2007 Nobel Prize nomination. Al Gore was also listed at number nine on the Environment Agency’s “Top 100 Green Campaigners of All Time” list.

Though they may not agree with all of his views, even Al Gore’s critics will admit that, given his position and political history as well as his outspoken views, he is certainly one of the world’s most influential environmentalists.