Law behind Bonfire Night among records sent from parliament to National Archives

Collection gems include 1605 Thanksgiving Act passed after Guy Fawkes’s failure and the longest act in the archives

As Bonfire Night approaches and firework displays light up the UK, in a file on a shelf in the labyrinthine National Archives can be found a flat vellum page, inscribed in exquisite calligraphy, and the origin of this week’s explosive celebrations.

The 1605 Thanksgiving Act was passed by James I after Guy Fawkes’s failure to assassinate the king, the Lords and the Commons, at the opening of parliament that year.

Celebrating the “miraculous and gracious deliverance” of the Protestant church from the “malignant and devilish papists”, it directed that church services be held every 5 November to commemorate the failure of the “Gunpowder Plot”.