What Is: the Privy Seal

Today we have several ways of verifying a signature and proving the identity of someone, from written ID to passwords, to handwriting analysis.  In Medieval times, the best way of verifying that someone signing a document was who they said they were, that they had the right to issue the document, and that copies of the document were legitimate was by affixing a wax seal to it.  No document, from charters and deeds, to writs and royal decrees, was considered legitimate, authentic and binding unless it bore the seal and/or the signature of the person who signed it.  Indeed, even if an individual couldn't sign his or her name, a seal was still sufficient proof that the document had passed under the seal, issued by the person whose seal was attached.

Nowhere was this more important than when kings issued charters, writs and decrees.  The King possessed two seals, the Great Seal of England, and his personal seal.  For security's sake, the great Seal was required to remain in the Chancery in London or Westminster.  However, the King, who often traveled around his dominions, had to have a means of attesting his personal approval to any documents issued in his name.  Beginning with the reign of King John, 1199-1216, the King's private seal, or Privy Seal, became the means for the King to execute documents in his name.  Depending on what the document was, it needed to be passed under the Great Seal as well as the King's Privy Seal.  Other documents bore the Privy Seal alone.  It was important enough that, in 1312, during the reign of King Edward II, the barons wrested control of the King's Privy Seal from him and assigned it to a member of the Council who became known as the Lord Privy Seal, the keeper of the King's seal.  From then out, kings affixed their signet to documents as a means of authenticating their signature, and the Signet was kept by the King's private secretary. 

Edward II had a hard time holding onto his own seal no matter who kept it.  In 1322, he was nearly captured at the Battle of Old Byland by the Scots.  Edward fled, but his personal seal was left behind to be taken as a trophy by Robert Bruce.  Only during Victoria's reign in 1884 did the legal significance of the Privy Seal cease.  By the Great Seal Act, documents no longer needed the King's Privy Seal to become law or legally binding.  The Office of Lord Privy Seal still remains in England as a Great Office of State.