LONDON, (Reuters Life!) - Four 13th century copies of the Magna Carta, considered to be one of the most important documents in the history of democracy, go on public display next week for the first time in nearly 800 years.

A copy of the Magna Carta, issued in 1217 by the guardians of Henry III, is seen in this undated handout photo made available by the Bodleian Library in London December 6, 2007. Four 13th century copies of the Magna Carta, considered to be one of the most important documents in the history of democracy, go on public display next week for the first time in nearly 800 years. REUTERS/Bodleian Library/Handout

The four, three of which date from 1217 and one from 1225, are held by Oxford University’s Bodleian Library and represent nearly one quarter of the surviving 13th century Magna Carta manuscripts in the world.

“These three 1217 charters are a unique historical collection,” said librarian Sarah Thomas. “No other institution can boast such a concentration of Magna Cartae.”

The Magna Carta was signed by England’s King John at Runnymede near Windsor just to the west of London in 1215 under intense pressure from rebellious barons who had captured London in protest at his exercise of arbitrary power over them.

In return for the concessions granted in the charter which effectively assured the barons of their feudal rights, the barons pledged allegiance to the English throne.

While it contains few sweeping statements of principle, it did establish in writing for the first time that the power of the monarch did have limits.

As such it is considered to be one of the cornerstones of democracy despite the fact that in restating feudal laws it has little or nothing to do with either human or equal rights.

Only four copies of the original charter dated 1215 survive, of which two are held by the British Library.

But the document was reissued regularly by or on behalf of succeeding monarchs, and only 17 of those dating from the 13th century now survive.

Apart from the four held by the Bodleian Library -- which houses more than eight million books and many other manuscripts -- the others are held at nine locations in Britain, Australia and the United States.

The Bodleian’s collection will go on public show for just six hours at Oxford’s Divinity School on Tuesday December 11. ahead of a sale on December 18 by Sotheby’s in New York of a copy of the Magna Carta owned by Ross Perot and priced at up to $30 million.