This nation annually celebrates the anniversary of a failed, circa 1605 attempt to assassinate nearly every member of its government in an explosion:

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Every year on November 5, England celebrates Guy Fawkes Day to commemorate the foiled attempt to assassinate King James I in an explosion that was to be ignited by a cache of gunpowder stashed under the House of Lords. The day is named in honor of the would-be assassin who was discovered guarding the gunpowder in the hours leading up to the planned attack, which was referred to as "the Gunpowder Plot." King James was the intended target, but the explosion, planned to take place during the state opening of Parliament, would have certainly destroyed all or nearly all of the British government.

This Nation Annually Celebrates the Anniversary of a Failed, Circa