Over 950 rallies in at least 80 countries took place on Saturday, the largest being in Lisbon, Madrid and Rome with thousands also turning out in New York and Washington.
Violence broke out in the Italian capital, with 70 people injured, three of them seriously, and 12 arrests. In New York 88 people were arrested.
Unexpected support came from Italian central bank governor Mario Draghi, a former Goldman Sachs executive who takes over as European Central Bank president next month.
"They're angry against the world of finance. I understand them," he said at a meeting of G20 financial powers in Paris on Saturday, although he expressed regret at the violence.
Hundreds of protesters have stayed on to camp out in Frankfurt, Amsterdam and London, where they have pledged to stay outside St Paul’s Cathedral, near the City of London financial district, to express their anger at the banks’s role in the current economic crisis.