(39) No free man shall be seized or imprisoned, or stripped of his rights or possessions, or outlawed or exiled, or deprived of his standing in any other way, nor will we proceed with force against him, or send others to do so, except by the lawful judgement of his equals or by the law of the land.

This great-grandfather of the Due Process Clause was signed by King John -- at swordpoint -- almost 800 years ago, along with many other promises.  Copies of the great charter were made and sent to the various counties of England, and one of those copies, from the Lincoln Cathedral, is presently on exhibit at the Library of Congress.

Update (11/13):  Justice Scalia's opening address at the Federalist Society Convention was on Magna Carta and its importance in the development of constitutional law. 

Update 2 (11/15):  Justice Scalia's address is now available online.

(39) No free man shall be seized or imprisoned, or stripped of his rights or possessions, or outlawed or exiled, or deprived of his standing in any other way, nor will we proceed with force against him, or send others to do so, except by the lawful judgement of his equals or by the law of the land. - See more at: http://www.bl.uk/magna-carta/articles/magna-carta-english-translation#sthash.QZ07c2XJ.dpuf