It was the birth of the concept that nobody - including the king - was above the law, and that a fair trial was a right of all.

“What we now have in the U.S. Constitution, the Bill of Rights … the grandfather of all of that was this,” said Redden.

The Magna Carta was first written in 1215, and revised throughout the 13th century. It wasn’t confirmed as English law until 1297. Of 17 copies that still exist, all but this one are publicly owned. The only other copy outside England is on show in Australia’s Parliament.

With only two small holes in the animal skin it’s written on, Sotheby’s Magna Carta is considered in great condition.

It’s being sold on behalf of the Ross Perot Foundation, which bought it in 1983 for $1.5 million.

In another sale of history, Sotheby’s is expecting $10 million for a medal George Washington commissioned for his comrade in arms, the Marquis de Lafayette.

The one-of-a-kind honor, being sold Tuesday, bears an image of an eagle and the Latin motto, “He left everything to serve the republic.”