Protests against corporate greed, executive excess and public austerity began to gel into the beginnings of a worldwide movement yesterday as tens of thousands marched in scores of cities. The "Occupy Wall Street" protest, which started in Canada and spread to the US, and the long-running Spanish "Indignant" and Greek anti-cuts demonstrations coalesced on a day that saw marches or occupations in 82 countries.

Some protests were small, as in Tokyo, where only 200 turned up; some were large, as in Spain, where around 60 separate demonstrations were staged; and some were muted, as in London, where nearly 2,000 intending to march on the Stock Exchange obeyed police who turned them back. As dusk fell, some 500 of them were kettled in St Paul's churchyard.

Containment tactics were also used by police in New York last night as thousands of demonstrators were penned behind barricades in Times Square. They had marched through Manhattan and protested outside the city's banks, withdrawing their money as they did.

Only one of the protests, in Rome, was violent. Here, among an estimated 100,000 protesters, were a few who broke away and hurled bottles, smashed shop windows, torched cars and attacked news crews. There were reports that the defence ministry had been partly trashed. Most of the disorder took place near the Colosseum, and police charged the protesters and fired water cannon. Some demonstrators fled, but others turned against the troublemakers, trying, with limited success, to stop them. Italy, with a national debt ratio second only to Greece's in the 17-nation eurozone, is rapidly becoming a focus of concern in Europe's debt crisis. But even in Germany – part of the solution to the crisis rather than the problem – around 4,000 people marched through the streets of Berlin with banners that urged the end of capitalism. Some scuffled with police as they tried to get near the country's parliamentary buildings. In Frankfurt, continental Europe's financial capital, some 5,000 people protested in front of the European Central Bank.

In Spain, six marches were set to converge on Madrid's Puerta del Sol plaza just before dusk yesterday. This is the country where, in May, groups which became known as the Indignant Movement established the first around-the-clock protest camps that lasted for weeks in cities and towns. Portuguese angry at their government's handling of the economic crisis were due to protest in central Lisbon later yesterday evening. Portugal is one of three European nations – the others being Greece and Ireland – that have already needed an international bailout.

In Stockholm, 500 people gathered to hear speakers denounce capitalism at a peaceful rally. They held up red flags and banners that read: "We are the 99 per cent" and "We refuse to pay for capitalism's crisis". The reference was to the world's richest 1 per cent, who control billions in assets, while billions around the world live in poverty or are struggling economically. Bilbo Goransson, a trade union activist, declared through a megaphone: "There are those who say the system is broke. It's not. That's how it was built. It is there to make rich people richer."

Anti-banking protests outside St Paul's cathedral yesterday drew a crowd of around 2,000. The "Occupy London" protesters gathered with the intention of taking over the plaza in front of the London Stock Exchange but were turned back at Temple Bar by mounted police. The crowds returned to St Paul's churchyard where WikiLeaks' Julian Assange spoke briefly.

The singer Billy Bragg was also in the crowd. "Today is about accountability," he said. "People want to see a change in the way things are done." He believed yesterday's protest represented a shift in the way the public views demonstrations. "I think the attitude coming out of protests here and on Wall Street has been incredibly positive," he said. "It's a desire to build, rather than smash things up."

In Canada, hundreds gathered in Toronto's financial district to decry what they said was government-abetted corporate greed which has served elites at the expense of the majority. Further protests were planned yesterday for other Canadian cities, while, in the US, marches were scheduled in cities large and small, from Providence, Rhode Island, to Little Rock, Arkansas; from New York to Seattle. In the Bosnian city of Sarajevo, there was a different tone: hundreds walked through the streets carrying pictures of Che Guevara, old communist flags and placards that read: "Death to capitalism, freedom to the people".

Turnout was light in Asia, where the global economy is booming. In Sydney, around 300 people gathered, cheering a speaker who shouted: "We're sick of corporate greed! Big banks, big corporate power standing over us and taking away our rights!" Only 200 people protested in Tokyo; and in the Philippines, about 100 people marched on the US embassy in Manila to express support for the Wall Street protests.

A group of 100 prominent authors, including Salman Rushdie, Neil Gaiman and the Pulitzer prize-winning novelists Jennifer Egan and Michael Cunningham, signed an online petition declaring their support for "Occupy Wall Street and the Occupy Movement around the world". And there were stinging words yesterday in The New York Times' leading article for David Cameron and George Osborne. It began: "For now, Britain's economy has been stuck in a vicious cycle of low growth, high unemployment and fiscal austerity. But unlike Greece, which has been forced into induced recession by misguided European Union creditors, Britain has inflicted this harmful quack cure on itself."

It ended: "Austerity is a political ideology masquerading as an economic policy. It rests on a myth, impervious to facts, that portrays all government spending as wasteful and harmful, and unnecessary to the recovery. The real world is a lot more complicated. America has no need to repeat Mr Cameron's failed experiment."