A crowd of about 400,000 protesters from across Europe marched here today against a presumptive war on Iraq and plenty of other things as well -- globalization, cultivation of genetically modified foods, commercial control of the Internet, copyright laws, Israel's policies toward the Palestinians and liberalization of employee layoff rules.

The massive march was peaceful, unlike several past anti-globalization rallies around the world. Organized under the sponsorship of the European Social Forum, a coalition of "no-global" movements, it attracted the support of far-left Italian parties and the country's biggest trade union, which bused in 120,000 demonstrators.

The march was heavy on shrill whistles, communist hymns, red flags and portraits of Ernesto "Che" Guevara. None of the marchers shared the Bush administration's enthusiasm for overthrowing President Saddam Hussein of Iraq, and instead held aloft banners proclaiming "Drop Bush, Not Bombs," "Stop Global War" and "The Real Terrorist is the West."

The U.N. Security Council's adoption Friday of a resolution ordering Iraq to disarm was widely regarded among the protesters as a pretext for a U.S.-led war. "We no longer have any illusions about institutions like the United Nations," said Alain Krivine, a French leftist.

"All the United States wants is oil to fuel their big cars," shouted Andrea Morettini, a student.

The turnout in Florence eclipsed both an anti-war rally held in London this year and an anti-globalization protest at the Group of Eight summit in Genoa last year. Violence and vandalism marred Genoa's march, as protestors tried to storm summit headquarters and police shot and killed one youth as he prepared to attack a carabinieri jeep with a fire extinguisher.

Today's march was the climax of four days of meetings. Participants gathered in the massive Fortezza di Basso, a fortress near the city's train station, and other locations before joining in the march. Organizers' estimates of the crowd far exceeded the official number.

Preparations for the march had been a source of controversy for weeks. Film director Franco Zeffirelli, a native of Florence, demanded that the protesters take their business elsewhere. Another Florentine, Oriana Fallaci, a celebrated interviewer and writer, called on the city to turn its back on the protesters, whom she labeled "fascists and nazis."

Florence had braced against possible violence and damage to its trove of Renaissance monuments. City workers built protective scaffolding around a replica of Michelangelo's David in Piazza della Signoria and fenced off other sculptures in a nearby loggia. Scores of businesses shuttered their storefronts, banks shielded automated teller machines, and McDonald's restaurants took down their golden arches. About 7,000 police stood discreetly if watchfully aside.

Demonstrators showed their disdain for Florentines who shut their businesses by scrawling insulting graffiti on walls and protective plywood window coverings. "Shame," wrote one on a shutter at the Black Molly Bar. "Closed out of ignorance," wrote another. Marzio's Beauty Salon on Via Francesco di Sanctis stayed open in a display of solidarity, according to its owner. Two customers in curlers applauded demonstrators as they passed, and the marchers responded with samba movements and raised fists.