( CNN ) Just days after four Magna Cartas were united for the first time in 800 years at the British Library in London , another ancient version of the document has been discovered by chance in a medieval coastal town in England . Mark Bateson , an archivist in Sandwich , southern England , found the previously unknown version of the Magna Carta -- which established the principle that everybody , including the king , was subject to the law -- after historian Nicholas Vincent had asked him to look for a separate document dealing with a local forest that he was researching . After rummaging through a scrapbook of council archives , Bateson found the Forest Charter , a document issued by King Henry III in 1217 , as well as a tattered page that he thought looked like the Magna Carta . `` He was n't really aware of the fact that they were either rare or that this one was indeed what it purported to be . I think , from his point of view , it was all a bit of a shock , '' said Vincent , professor of medieval history at the University of East Anglia . But he says there is no doubt that this is a version of the Magna Carta , or `` The Great Charter , '' that was published in 1300 under the reign of King Edward I . The original document was issued by England 's King John in 1215 . The document is badly damaged , with a third of its text and the royal seal of Edward I missing and the back of it firmly stuck down . But despite its deformities , Vincent said it could fetch millions . `` It [ the damage ] probably would interfere with the value of it if someone were foolish enough to sell it , '' he said . `` But I think there 's no question of that . `` This one is in nothing like the condition of the one that went for sale in New York [ in 2007 , for $ 21.3 million ] but I would say it 's certainly worth in the millions rather than in the tens and hundreds of thousands . And as a pair , they are all the more desirable . '' And other discoveries have been made as well . `` The fact that they [ Magna Carta and Forest Charter ] are both there in Sandwich is particularly interesting because there is no royal forest in Kent . That really tells us something that we really did n't know before about the way that the document was published , '' Vincent said . `` And given that this is the most important document in English history , people make such a fuss about it , to find out anything new about it is rather exciting . '' This is a hugely significant gain for Sandwich . `` Through the American Declaration of Independence , continuing in the Universal Declaration of Human Rights , Magna Carta still underpins individual liberties worldwide , '' said the town 's mayor , Paul Graeme . To own such a document , and the Charter of the Forest , is an honor and a great responsibility . '' `` What matters is Sandwich now becomes one of a very small number of institutions -- there are only about a dozen -- that own a Magna Carta , '' said Vincent . `` There are lots and lots of institutions across the Atlantic and elsewhere in the world that would love to have this document . ''
A version of the Magna Carta published in 1300 has apparently been found in an English town . The document was discovered by chance in council archives . Historian Nicholas Vincent said `` it 's certainly worth in the millions ''