A new generation of global activists have embraced the image of a 17th century English Catholic traitor whose arrest and gruesome execution is still celebrated across Britain every year by burning his effigy.

White caricature masks of Guy Fawkes -- who was hanged, drawn and quartered for attempting to blow up England's parliament in 1605 -- have been appearing online and on the streets of London, New York and Madrid among protesters against the financial crisis.

While many Fawkes masks sold in Britain this week may end up in their traditional places on dummy Guys cast onto bonfires and as part of fireworks displays at the hugely popular annual Nov 5 Guy Fawkes Night celebrations on greens and in parks throughout the UK, many more may be worn at demonstrations.

The masks were popularised by the 2006 film V for Vendetta -- in which a masked hero of the future uses the Fawkes image as he attacks the government. Now the stylised, gleaming white, grinning and bearded visage has become the face of the leaderless Anonymous movement.

They have become an increasingly popular sight at the anti-banking Occupy Wall Street protests that have spread across the United States and into other countries including Britain, as well as an increasingly common presence online.

Traditionally, Guy Fawkes has simply been seen as the original terrorist or just a quaint figure we commemorate once a year, said Cathy Ross, director of collections and learning at the Museum of London. The idea of seeing him as a more relevant, radical figure is something new.

For centuries, English school children have been taught to: Remember, remember the fifth of November...gunpowder treason and plot and Fawkes has always been the ghost which has haunted a nation that is only now changing discriminatory laws which bar potential heirs to the throne from marrying a Catholic.

Fawkes hoped his attack -- foiled at the last minute after his stash of gunpowder was discovered under parliament -- would usher in a popular Catholic revolt, but the aims of those wearing his mask these days appear less focussed.

Initially, Anonymous appeared a purely online force, attacking those it believed were attempting to stymie free speech in the name of intellectual property or national security. Last year, it declared virtual war on websites such as that of global credit card firm MasterCard.

VIOLENT, LIBERTARIAN IMAGE

But with Spain's indignados protests against austerity, the popularity of the masks leapt -- to the extent that costume shops in Spain sold out almost overnight and activists were forced to order in from overseas.

Both the masks and the Anonymous group themselves have since also joined forces with the occupy movement, although it is far from clear that all who wear them sympathise with Anonymous.

It's a very powerful, violent symbol, says Tim Hardy, founder of UK activist blog Beyond Clicktivism. It's very anti-parliamentarian, very anti-establishment, libertarian rather than leftist. Beyond that, it's hard to say what it stands for. Many of those who wear it are very young.

For now, the methods of those wearing his image have been much less violent than those unsuccessfully attempted by Fawkes. Had his attack on the State opening of Parliament on November 5, 1605 succeeded, he would have killed not just King James I but also almost the whole parliament, church leaders and wider ruling hierarchy.

Some worry that might change. The U.S. Department of Homeland Security warned last month that there was a risk hackers from Anonymous might target crucial industrial control systems of power plants and other key infrastructure, causing chaos. Some activists, however, were sceptical, accusing authorities or scaremongering and trying to demonise the group.

Still, there have been some reports which said that Anonymous was attempting to organise an attack on social networking site Facebook for November 5 itself, ironically organised in part via Facebook itself.