Speakers told the crowd of about 200 at a warehouse near Chicago's Chinatown district that the United States and NATO supported policies that hurt working-class folks in developing nations.
"All the demands that we're making -- for social justice, economic equality, against the wars and occupations -- they're all linked by opposition to a system that's out of control," Ashley Smith, who flew to Chicago from Vermont, told the Chicago Tribune.
Smith was one of a number of out-of-towners bolstering the ranks of Occupy Chicago for the high-profile summit.
Another visitor, 19-year-old Kevin Rambo, told the Trib he was representing Occupy San Diego and was drawn to the NATO event. "There's a revitalized activist community because of the Occupy movement, for the most part," he said. "Because of the growing number of people who are getting involved, I couldn't really not protest against NATO."
No specific plans to demonstrate or disrupt the NATO summit were announced, the newspaper said. After the welcoming speeches, the attendees participated in various workshops on issues such as the legal system and education.