This is the story of the first Earth Day—and why it mattered (2024)

Each year on April 22, people around the globe come together to honor and conserve their shared home: Earth.

Known as Earth Day, the holiday got its start in the United States in 1970 as a teach-in on college campuses. It has since evolved into a global celebration of the environmental movement’s achievements—and a reminder of the work yet to be done.

(5 simple things you can do to live more sustainably.)

The same wave of activism that led to the creation of Earth Day also ushered in a new age of environmental legislation—one that saw the passage of the Clean Air Act and Clean Water Act as well as the creation of the Environmental Protection Agency. Here’s how Earth Day came to be a holiday—and why activists hope it will continue to shape a more sustainable future.

When was the first Earth Day?

The 1960s was a decade of environmental awakening for much of the United States. Most Americans were introduced to the effects of air pollution in 1962 when naturalist and former marine biologist Rachel Carson published Silent Spring. In the influential book, Carson meticulously chronicled how DDT, a then-widespread pesticide, entered the food chain and caused cancer and genetic damage in humans and animals.

Silent Spring was an instant bestseller, causing people to question modern technology’s impact on the environment, while setting the stage for the environmental movement to accelerate.

(What you need to know about pesticides and other toxic waste.)

One of the original titans of the environmental movement was the father of Earth Day, former Democratic Senator Gaylord Nelson from Wisconsin. A staunch progressive and wilderness lover, Nelson made it his priority to pass environmental legislation like the 1964 Wilderness Act, which safeguarded federal land, and the 1968 Wild and Scenic Rivers Act, which established a process for protecting free-flowing rivers.

Then, in January 1969, a devastating oil spill in Santa Barbara, California, inspired Nelson to spearhead a new grassroots approach to the environmental movement. The oil spill, which killed thousands of birds and stained beaches along the California coast, was the largest the U.S. had seen at the time and remains the worst in California’s history.

Stirred by the energy of students participating in anti-war protests, Nelson set out to galvanize the same kind of action on behalf of the environment. He pitched an idea for a teach-in—dedicated discussions between faculty and students about the environment. He selected April 22, 1970, a date between Spring Break and final exams, to allow for maximum student participation.

Nelson recruited Pete McCloskey, a California Republican representative, and Denis Hayes, a young activist, to help organize the sit-in. Soon, the effort ballooned into what is now dubbed the Earth Day protest. By April 22, interest had grown so much that 20 million Americans at 2,000 colleges and universities and 10,000 grade schools participated in the first Earth Day through demonstrations, decluttering rivers, and more.

Polls from the time showed that concern for the environment had leapt to the forefront of public opinion—with air and water pollution even perceived as more important than issues of race and crime. In a 1971 poll, 78 percent of Americans indicated they would be willing to pay to clean up their air and water.

“The reason Earth Day worked is that it organized itself,” Nelson told the New York Times. “The idea was out there and everybody grabbed it. I wanted a demonstration by so many people that politicians would say, ‘Holy cow, people care about this.’”

Why is Earth Day so important?

While Nelson led the charge, the groundswell of public support for environmental legislation had generated widespread support in Congress and the White House. The momentum of the first Earth Day protest carried throughout the year—and amounted to some of the strongest environmental legislation to date.

By the end of 1970, President Richard Nixon signed into law the National Environmental Policy Act, the Occupational Safety and Health Act, and the Clean Air Act, which respectively lay the groundwork for government agencies to assess the environmental impact of their actions, set health and safety standards in workplaces, and allowed regulation of air emissions.

(The Clean Air Act saved millions of lives and trillions of dollars.)

To more effectively oversee and centralize any environmental regulations, Nixon created the United States Environmental Protection Agency—which was established just eight months after the first Earth Day.

Concern for protecting the environment continued throughout the 1970s as Congress passed the Clean Water Act, regulating pollutant discharges in U.S. waters, the Endangered Species Act protecting wildlife from extinction, and the Federal Insecticide, Fungicide, and Rodenticide Act, which regulated pesticides.

Nelson was at the center of most of these major environmental bills, specifically the Clean Air and Water Acts and the Endangered Species Act. He expanded his environmental activism and became a principal sponsor for laws that preserved the Appalachian Trail, established fuel efficiency standards, and banned DDT.

Just 10 years after the first Earth Day, Nelson wrote in the EPA Journal that predictions of the end of the golden era of environmentalism were preemptive and inaccurate.

(Forget your carbon footprint—your climate shadow is what really matters.)

“To anyone who has paid attention, it is clear that the environmental movement now is far stronger, far better led, far better informed, and far more influential than it was ten years ago. Its strength grows each year because public knowledge and understanding grow each year,” Nelson wrote.

The Earth Day movement went global for its 20th anniversary: Hayes organized a campaign that mobilized 200 million people to boost environmental issues and promote recycling through rallies and a drum chain in Gabon. This paved the way for a 1992 United Nations conference in Brazil focused on the environment, dubbed the “Earth Summit,” signaling a more serious effort from global governing bodies towards sustainability.

A few years later, Nelson’s contributions to the environment were honored in the form of a Presidential Medal of Freedom in 1995. Nelson continued to spearhead environmental activism in the new millennium, but this time he focused on the latest priorities: global warming and clean energy.

How is Earth Day celebrated?

Since its original conception as a teach-in, Earth Day has become a global phenomenon paving the way not only for protests and legislation, but also for volunteering and habitat clean-ups. The holiday now largely focuses on combating climate change. Its official site —which is managed by Environmental Action, Inc., the modern incarnation of the group that organized the first Earth Day—cites “climate change deniers” and “oil lobbyists” as two of the biggest hurdles for the modern movement.

Climate change continues to stir debate as Earth experiences a rise in the frequency of wildfires, extreme storms, and harsh weather, which also has increased the number of displaced communities. The UN’s Intergovernmental Panel on Climate Change published a report in 2022 urging immediate action to slow the effects of climate change, warning of severe health consequences and worsening social inequities

(Meet the young activists demanding climate action.)

While scientists nurture nature to help slow the effects of climate change, activists continue to raise the alarm. Young people in particular are leading the charge both on college campuses and in the international sphere through prominent voices like Greta Thunberg.

“I don’t want your hope, I don’t want you to be hopeful,” Thunberg famously said at the 2019 World Economic Forum in Davos, Switzerland. “I want you to panic and act as if the house was on fire.”