ROBERT SIEGEL, HOST:
Now the clever bit of marketing that helped launch the environmental movement 45 years ago today. Earth Day was coined by one of the most well-known admen in America, Julian Koenig. As Reid Frazier found out, the story of how Earth Day got its name shows the power that just two words can have.
REID FRAZIER, BYLINE: If you're over a certain age, you've almost certainly heard this phrase...
(SOUNDBITE OF TIMEX AD)
UNIDENTIFIED MAN: Timex - it takes a licking and keeps on ticking.
FRAZIER: This was one of many ad campaigns dreamed up by Julian Koenig. His tagline for the Volkswagen Beetle - think small - was voted the most successful ad of the 20th century by Ad Age Magazine. But he was also an environmentalist. In early 1970, he found out about a group organizing a nationwide event they were calling an environmental teach-in. Historian Adam Rome.
ADAM ROME: They all thought that environmental teach-in was a loser of a name, that it sounded too academic, that it didn't sound action-oriented.
FRAZIER: Koenig volunteered to help market the event. He gave the group a few choices for what to call it. Denis Hayes was the campaign's young national director.
DENIS HAYES: One of them was for Earth Day. One of them was for E-Day. One, I think, was for Ecology Day. But he made it clear that he thought that the one that worked best was Earth Day.
FRAZIER: Hayes says the name was key to bringing more people in. The event wasn't a debate or a lecture.
HAYES: If you're starting to talk about human ecosystems and biomes, you relatively quickly put your audience to sleep. We needed some way to describe this that would resonate immediately and people would know what it is you're talking about, and Earth Day did accomplish that for us.
FRAZIER: The group placed an ad in The New York Times. The ad and the name helped achieve a massive turnout - 20 million people.
HAYES: I figured oh, my God, we have - we've unleashed some powerful new force now on American life. And it turned out to be true.
FRAZIER: Julian Koenig's daughter, Sarah Koenig, is a producer for "This American Life" and host of the podcast "Serial." She says Earth Day typified her father's best work.
SARAH KOENIG: Very spare, very smart, very classy, very simple, you know - but simple, but smart - I mean, think small, right? Like, that's his most famous line. It's two words.
FRAZIER: Despite his success, Julian Koenig was conflicted about his profession. He told his daughter this in a 2009 story she produced for "This American Life." Advertising, he told her, was built on deception.
(SOUNDBITE OF RADIO SHOW, "THIS AMERICAN LIFE")
JULIAN KOENIG: And I don't think anybody can go proudly into the next world with a career built on deception, even though - no matter how well they do it.
FRAZIER: But there was one bit of advertising he did feel good about.
(SOUNDBITE OF RADIO SHOW, "THIS AMERICAN LIFE")
J. KOENIG: Well, Earth Day is one of the things when my children say what did you do in the Great War, Grandpa? I'll say well, I wrote Timex, it takes a licking and keeps on ticking, and I wrote think small in the first Volkswagen advertising, and I named Earth Day.
FRAZIER: Julian Koenig died last year. He was 93. Of all his many ads, the one with the longest shelf-life, it turned out, was Earth Day. For NPR News, I'm Reid Frazier. Transcript provided by NPR, Copyright NPR.