About 200 protesters, many from London's anti-capitalist Occupy movement, marched to Parliament on Guy Fawkes Day, the annual commemoration of the English anarchist who tried to blow up the building in the 17th century.
Many of Saturday's protesters were wearing a grinning, somewhat sinister mask of Guy Fawkes that has become an icon of the Occupy Movement around the world. The rally was largely peaceful, but the group was kept from getting close to Parliament by a heavy police presence.
Some activists said that donning the masks is a way of reminding governments that authority can be challenged by the masses. "I think people are giving a polite nod to a kind of violent radicalism," said Laurie Penny, a blogger and frequent protester.
Many of the demonstrators had marched from St. Paul's Cathedral in London, where the Occupy movement has set up camp for weeks to protest social inequality and the excesses of the banking industry.
Saturday's rally coincided with Guy Fawkes' Day, which is celebrated every year in England on Nov. 5 with bonfires and fireworks to mark the failure of the plot hatched by Fawkes and other conspirators to destroy Parliament with explosives in 1605.
Some regard Fawkes as a folk hero, and Saturday's protesters have a similar political message to his: Rebel against state power.
Fawkes is a household historical name in England for plotting with 12 others to destroy Parliament, assassinate King James I and install a Catholic monarch in the botched "Gunpowder Plot."
The conspiracy fell apart when authorities found out about it and caught Fawkes guarding barrels of gunpowder in the cellar of Parliament. Fawkes was tried as a traitor, and the king's narrow escape has been celebrated every year on Nov. 5, with fireworks and the burning of effigies known as "guys" across the country.
In Britain and elsewhere, Fawkes' story -- or rather a popular culture version of it -- has been seized upon as a potent symbol by two increasingly popular anti-government movements.
Stylized Guy Fawkes plastic masks, with a clownish, sinister mustachioed smile and features loosely based on drawings of the anarchist, have been worn by hundreds of antiestablishment protesters from the Occupy Wall Street movement from New York to Hong Kong. Before that, members of the international rogue collective of "hackivists" known as Anonymous had worn the now instantly recognizable masks during protests against the Church of Scientology.
The masks owed their popularity not so much to Fawkes' story, but to the comic book-turned-movie "V for Vendetta," which features a violent, anarchist freedom fighter who fashions himself a modern day Guy Fawkes and rebels against a fascist government. The end of the movie included a scene in which thousands all wearing the masks marched on Parliament, watching it explode spectacularly.
On Saturday, Penny said the masked activists are sending home the message in "V".
"It's about the power of a shared idea in overcoming state control," she said.
Meanwhile Anonymous, which has made a name for itself by launching cyber attacks on government and large corporate websites, also seized on Guy Fawkes Day by backing an online campaign urging people to collectively withdraw their money from large banks Saturday in a bid to show their anger against the banking sector. Activists have dubbed Saturday "Bank Transfer Day" and "Operation Cashback."
In Britain, the nursery rhyme "Remember, remember, the fifth of November/Gunpowder, treason and plot" is familiar to most as a warning that treason would never be forgiven.
But modern Guy Fawkes Days -- also called Bonfire Night -- rarely evoke the violent story, and instead typically focus on fun fairs and fireworks.