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”.

It is one of several documents relating to Britain’s most famous treason plot which are among 4m records transferred from the archives of parliament to the National Archives at Kew, south-west London, a project now complete five years after it first began.

“We often find that these acts have very flowery beginnings. The first section of the act lays out the reasons why the act is being instated. And then it goes into the actual legislation itself,” said Dr Graham Moore, an early modern parliament specialist at the National Archives.

“Often that can be quite florid. Here, for example,” he said pointing to one passage, “there is a little bit about King James I and VI and his loins, which is quite fun: ‘Sovereign Lord King James, the most great learned religious King that ever reigned therein, enriched with most hopeful and plentiful progeny proceeding out of his royal loins.’”

An incredibly well-preserved journal for the House of Commons, the precursor of Hansard, has a handwritten entry in the margin, as though an afterthought to official business of the day, and written by the Commons clerk on 5 November 1605. It tells of the search of the Palace of Westminster cellars, and the discovery of 36 barrels of gunpowder, along with Guy Fawkes.

A separate scroll reads: “An Act of Attainder of divers Offenders in the late most barbarous, monstrous, detestable and damnable Treasons.” This act declared Guy Fawkes and his co-conspirators to be guilty of treason, decreeing they were to be hanged, drawn and quartered.

“We see these little additions stitched on the vellum. It would have been laid in the house as a bill, and then edited as it was debated over. So, we often see these little additions, stitched on top, crossings out, and things like that, where it’s been changed,” said Moore.

The transfer of archives from their historic home in Victoria Tower at the Palace of Westminster to their Kew repository has been a mammoth undertaking over five years, adding 16.5 linear kilometres of records to the 174.5 linear kilometres of documents already housed there.

Now the move is complete, they are now fully catalogued, marked with their own individual registration barcodes, and available for the public to order and view for free at a venue more suited to their long-term preservation and more accessible.

They include a suffragette’s banner, from 28 October 1908, which was secretly taken into the Ladies’ Gallery in the Commons chamber. One suffragette dropped the banner into the chamber while two others chained themselves to the iron grille of the Ladies’ Gallery, shouting: “We have been behind this insulting grille for too long.” The grille had to be removed with the two still attached.

Not only documents have now been transferred. A piece of a gravestone, a sword and a uniform are among the more unusual items Kew’s archivists have to contend with.

The largest document is the 1821 Land Tax Commissioners Act, the longest act in the archives of parliament. It nominates 65,000 commissioners to collect revenue based on land valuations. Inscribed on 757 vellum membranes it totals 348 metres in length – more than three football fields.

Another, the Great Reform Act of 1832, is “a really important constitutional document that admits, for the first time, middle-class men in the borough towns to the franchise. So it’s sort of the first step on that long journey towards modern democracy,” said Dr Joe Cozens, a 19th century parliament records specialist at the National Archives.

The National Archives is now responsible for a total of 20m records, with one-third housed in deep storage at a facility in Cheshire. The chief executive, Saul Nassé, said: “The archives of parliament lived at the Palace of Westminster very happily for very many decades. But that wonderful building, of course, has not been designed with modern preservation standards in mind.”

With the National Archives already holding records from the judiciary and government, with the addition of parliament’s records, “you have the kind of three arms of the British state, all in one place”. It was “quite a significant thing, given the way our democracy operates”.

“It offers the public more access than ever before,” he said. “There’s no point in creating records, keeping them safe, unless you find a way of bringing them to life for people.””