On September 17, several hundred people marched to an empty square in Lower Manhattan—a place so dull that the bankers and construction workers in the neighborhood barely knew it was there—and camped out on the bare concrete. They would be joined, over the next two months, by thousands of supporters, who erected tents, built makeshift institutions—a field hospital, a library, a department of sanitation, a free-cigarette dispensary—and did a fair amount of drumming.

It was easy to infer from the signs protesters carried what the grievances that gave rise to Occupy Wall Street were: an ever widening gap between rich and poor; a perceived failure by President Obama to hold the financial industry accountable for the crisis of 2008; and a sense that money had taken over politics.

The amazing thing about the Occupy Wall Street movement is not that it started—America was full of fed-up people at the end of 2011—but that it worked. With a vague agenda, a nonexistent leadership structure (many of the protesters were anarchists and didn’t believe in leaders at all), and a minuscule budget (as of December, they’d raised roughly $650,000—one-eighth of Tim Pawlenty’s presidential campaign haul), the occupiers in Zuccotti Park nevertheless inspired similar protests in hundreds of cities around the country and the world. What they created was, depending on whom you asked, either the most important protest movement since 1968 or an aimless, unwashed, leftist version of the Tea Party.

Occupy Wall Street quickly attracted intellectual celebrities—and, eventually, actual celebrities—but its founders were an unlikely assortment of stifled activists, part-time provocateurs, and people who simply had no place else to turn. There was Kalle Lasn, who ran an obscure Vancouver-based magazine called Adbusters with just 10 employees and an anti-consumerist agenda. Another key organizer, Vlad Teichberg, was a 39-year-old former derivatives trader who spent his weekends and evenings producing activist video art. David Graeber, an anthropologist at the University of London, quickly emerged as the movement’s intellectual force. If he was known at all, it was not for his anarchist theories or for his research into the nature of debt, but for being let go by Yale in 2005—in part, he believes, on account of his political leanings.

It is unclear whether the impact of Occupy Wall Street will be lasting or brief. But the story of how these unlikely organizers—and the activists, students, and homeless people who joined them—managed to seize control of the national conversation is remarkable, miraculous even. This is how it happened.

I. “Hello, Citizens of the Internet”

VLAD TEICHBERG

Former derivatives trader; co-founder, Global Revolution

People think this started in New York on September 17, but that’s not true. From my point of view, it started in Egypt.

JEFFREY SACHS

Economist, Columbia University

I was in Egypt after Tahrir Square, talking to young people who had accomplished something completely amazing. Two thousand eleven was a year of global upheaval—I’d seen it everywhere. And a number of times in the spring, I said in interviews: Don’t be so sure that this can’t happen here. Because the precursors—of inequality, of a sense of injustice—apply to the U.S.

KALLE LASN

Co-founder, Adbusters

The left had been chattering on about revolutions for a long time, but we’ve basically been howling at the moon. And then, all of a sudden, a bunch of young people [in Egypt] using social media were able to mobilize not just 500 or 5,000 people, but 50,000 people. They inspired us with their courage and with their techniques.

In our brainstorming sessions at Adbusters in February and March, we said, “Isn’t some sort of regime change possible in the United States of America?” It wouldn’t be a hard regime change like what happened with Mubarak, who was basically torturing people every day. We called it a “soft regime change.”