how did it fail?
The plan was revealed through an anonymous letter sent to William Parker.
Gunpowder Plot

The plot was revealed to the authorities in an anonymous letter sent to William Parker, 4th Baron Monteagle, on 26 October 1605
what is guy fawkes night? An annual commemoration day . why is it celebrated? It is celebrated for the failure of an attempt on the life of King James I. when is the occasion? On 5 November every year. why is it named so? It is named after Guy Fawkes.who was arrested and the attempt of murder was foiled. who is that prisoner? A member of a group of English Catholics involved in the failed Gunpowder Plot. where was he born? Stonegate, York. what is the plot about? The plan was to blow up the House of Lords during the State Opening of Parliament on 5 November 1605, as the prelude to a popular revolt in the Midlands during which James's nine-year-old daughter, Elizabeth, was to be installed as the Catholic head of state.
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Gunpowder Plot [SEP] Introduction
Most of the conspirators fled from London as they learned of the plot's discovery, trying to enlist support along the way. Several made a stand against the pursuing Sheriff of Worcester and his men at Holbeche House; in the ensuing battle, Catesby was one of those shot and killed. At their trial on 27 January 1606, eight of the survivors, including Fawkes, were convicted and sentenced to be hanged, drawn and quartered.