After an oil spill off the coast of Santa Barbara, Calif., in 1969 — the largest oil spill in U.S. history at the time — Sen. Gaylord Nelson of Wisconsin and Rep. Pete McCloskey of California formed a nonprofit group called Environmental Action.

The first goal of the group was to hold a national teach-in day about the environment. A nine-person staff was assembled in Washington, D.C., to get the word out about the day, which was scheduled for April 22, 1970, and dubbed “Earth Day.”

Bryce Hamilton, an Iowa native who now lives in Minneapolis, was chosen for that elite staff. Then 28, Hamilton was named coordinator of high school activities.

Hamilton’s job was to connect with school-age students around the country by answering phone and mail requests from students and sending them information packets to help them plan Earth Day observations.

“Americans are becoming angry, angry that their rivers are being used as sewers, that their beaches are black and oily, and that their wetlands and natural areas are being swallowed up by voracious land developers,” Hamilton wrote in an emotional letter to students to get them thinking.

“… As a concerned student, you have a unique opportunity to promote environmental awareness where it is much needed — in your school, home and community.”

He included a long list of actions students might take, including learning about pending anti-pollution bills, making posters and banners, starting a newsletter and taking field trips led by conservationists and biologists.

Long before the advent of social media, Hamilton said the idea caught on quickly.

“It’s not a word that was used then, but [the movement] went viral,” said Hamilton, who had served in the Peace Corps in Guatemala.

“In a little over three months, it really spread.”

At the end of January 1970, the first full month in operation, Hamilton and the group had heard from 300 high schools. By mid-February, that number had grown to 1,200.

Among the letters that arrived in early February was one from a group of high school students in Cloquet, Minn. The group said it was going to hold a weeklong schedule of activities with speakers, films and field trips.

“I had the best job in the office,” Hamilton said. “I would open an envelope and read the letter and say, ‘Oh, my gosh,’ and I would share it with the office. These kids were socially conscious at an early age.”

Hamilton said the office received many poignant letters from preteens and teens. He saved copies of some of the letters.

A fifth-grader from Pennsylvania wrote, “Please send all the information you have on Earth Day. I … would like to organize my community. The teachers and adults of my area are less aware of the urgency of this problem than the children and I would like to help make them aware.”

A 12-year old from Detroit wrote, “I would like to know how I can help stop pollution.

“The word ‘pollution’ was the one word you heard all the time,” Hamilton said. “It really caught on.”

And not just with kids.

“It spanned multigenerations,” Hamilton said. “It was very positive. People were upset about the environment and knew we needed to take action.”

Interest in the day spanned from coast to coast. On April 22, 1970, according to published estimates, 20 million people (almost 10% of the nation’s population of 205 million in 1970) took part in activities.

In Minnesota, Gov. Harold LeVander told students at West St. Paul Junior High School, “We must use our precious resources wisely, if we are to survive.”

Several things came out of the first Earth Day, Hamilton said.

“By the end of the year, the Environmental Protection Agency (EPA) had been created,” he said. “And several other organizations started. It really raised consciousness around the world. Eventually, Earth Day was celebrated internationally, as well.”

After that first Earth Day, Hamilton worked for several years as an environmental consultant and educator. He and his wife, Donna, owned a small business.

For the 50th anniversary of Earth Day — Wednesday, April 22 — Hamilton said the hope was “that millions would gather around the world.”

The coronavirus pandemic has made that impossible. But Hamilton remains hopeful.

“Maybe it can be celebrated later this fall,” he said, “or we’ll have to wait until next year.”

Hamilton is also optimistic because of a new generation of environmentally-conscious students motivated by teenage Swedish activist Greta Thunberg.

“I’m impressed immensely by her,” Hamilton said. “She has inspired lots of people, including adults. I can’t say enough about her. She has raised my spirits.”