Background
At that time, before the Thirty Years' War and after the Eighty Years' War, there was a lot of tension between various religions, and this was especially true for Guy Fawkes. Guy Fawkes converted to Catholicism, and he fought in the Eighty Years' War on Catholic Spain, as they attempted to crush the Protestant Dutch reformers. Guy Fawkes met Robert Catesby, who planned to assassinate King James I.
Event
Robert Catesby was a Catholic whose father was persecute by Queen Elizabeth I for refusing to conform to the Church of England. So, he and a lot of other people rented a cellar that also went under the House of Lords building.
At around midnight on the night of November 4-5, Sir Thomas Knyvet, a member of parliament, found Guy Fawkes lurking in a cellar under the Parliament building and ordered the police to search the area. 36 barrels of gunpowder were found, and Fawkes was taken into custody. Fawkes was tortured, and later he admitted that he was in a conspiracy to kill the Protestant King James I, and replace him with Catholic leaders.
Fawkes and the other conspirators were sentenced to be hanged. Moments before he was to be hanged, Fawkes jumped form a ladder, breaking his neck and dying. Following the Gunpowder Plot, Catholics couldn't vote, and many of their rights were restricted.
Guy Fawkes Day
In 1606, the British government declared that November 5th would be a day of thanksgiving. Called Guy Fawkes Night (or Guy Fawkers Day) is now celebrated around the United Kingdom in remembrance of the Gunpowder Plot. That night, citizens across the UK would light fires, and burn effigies of Guy Fawkes.