1570-1606. English conspirator in the Gunpowder Plot to blow up King James I and the members of both Houses of Parliament. Fawkes, a Roman Catholic convert, was arrested in the cellar underneath the House 4 Nov 1605, tortured, and executed. The event is still commemorated in Britain every 5 Nov with bonfires, fireworks, and the burning of the `guy', an effigy.