The earliest account of the notorious Gunpowder Plot - Guy Fawkes' attempt at destroying Parliament - is coming to auction at Sotheby's London on December 9.

The letter went out to ambassadors across Europe to pass on news of the failed assassination attempt, as well as to dispell any 'malicious discourse, and invention'

The document was written by intended victim Robert Cecil, Earl of Salisbury, on November 9, 1605 - just four days after the plot was rumbled. It is valued at £40,000-60,000 ($63,970-95,955).

Addressed to Sir Ralph Winwood, the letter sees Cecil describing the event as "the most cruell and detestable practise, against the person of his majesty, and the whole estate of this realme, that ever was conceaved by the hart of man."

Cecil, the secretary of state, wrote several such letters to ambassadors across Europe, passing on the news, as well as dispelling any "malicious discourse, and invention" against King James I.

Fawkes faced a grisly end 'yet coulde no threate of torture drawe him from any other language then this that hee is ready to dye, and rather wisheth ten thousand deaths, then willingly to accuse either his master or any other'

In Cecil's words, the Gunpowder Plot "intended, not onely the extirpation of the kings Ma[jes]ty, and his Issue Royal but the whole subversion and downefall of this Estate, the plott being to take away, at an instant, the King, Queen, Prince, Counsell, Nobility, Clergie, Judges, and the principall gentlemen of this Realme".

However, Fawkes was famously discovered in the tunnels under Parliament just 12 hours before the plan was due to be exacted.

He apparently gave the name John Johnson upon his arrest and was "no more dismayed then if he weare taken for a poore robberye, by the highe waye", despite facing torture in the Tower of London.

Fawkes was hung, drawn and quartered soon after.

Paul Fraser Collectibles has a number of important historical manuscripts for sale.