For many of us, Earth Day has been in our lives for so long that it’s easy to take for granted. Especially for readers born after its founding in 1970, the annual holiday likely conjures childhood memories of lighthearted educational activities and colorful posters illustrated in bright blues and greens. It’s rare that we think about the radical activism and aggressive political organizing that led to the creation of Earth Day itself, or the decades of unchecked industrial pollution and environmental destruction that inspired its founders. However, for clean energy advocates and environmentalists of every stripe, it’s important to remember and honor the crucial role that Earth Day has played in shaping the global sustainability movement we have today.
In the U.S., the decades prior to the first Earth Day were marked by the unprecedented prosperity and economic growth of the postwar era. America’s love affair with the automobile was at its peak, with Americans consuming incredible amounts of leaded gas. Pollution was seen as little more than a side effect of technological progress, and industrial manufacturers and power plants were free to pollute the environment without fear of repercussions. While the widespread political protests of the 1960s did lead to the emergence of some early environmental advocacy initiatives, those efforts were dwarfed by the massive anti-war movement, and splintered across individual causes like air pollution and wildlife conservation. As activist Denis Hayes, one of the original organizers of Earth Day, explained in a 2019 interview with TIME:“It sounds strange today, but back then, the folks involved with those various causes didn’t think of themselves as having anything in common with one another.”
This began to change in 1969 when former Wisconsin Senator Gaylord Nelson was witness to the incredible environmental damage caused by an oil spill that occurred that year in Santa Barbara, California. Taking inspiration from the student-led movements of the time, Senator Nelson began publicizing the idea of what he called “a national teach-in on the environment,” recruiting conservative congressman Pete McCloskey and Denis Hayes—then just a 25-year-old Harvard student—to help organize the event. The team settled on the name Earth Day with the help of a volunteer from a New York advertising agency, and chose April 22 as its date in an effort to secure the support of college students with time to spare in the weeks between spring break and final exams.
The first Earth Day took place on April 22, 1970, and brought together over 20 million Americans—ten percent of the total population—with enormous rallies and demonstrations taking place all over the country. That inaugural event was a stunning success, bringing disparate environmental causes together under one umbrella, and achieving remarkable bipartisan support. The first Earth Day is now widely credited for the passage of the Clean Air Act and the creation of the U.S. Environmental Protection Agency, both of which occurred later that year, as well as for the passage of the Clean Water Act and the Endangered Species Act, which came about just a few years later. In 1990, Earth Day became a global event with 141 countries and over 200 million people participating. Today, Earth Day ranks as the biggest secular observance in the world, and is celebrated by more than a billion people each year.