The last letter ever written by the teenage Irish rebel Kevin Barry will be one of the many items put up for auction at the annual "Independence Auction."
 
Kevin Barry was an 18-year-old medical student who was executed by the British for taking part in an IRA ambush that resulted in the death of three British soldiers during the War of Independence.
 
Barry's letter will be sold alongside thousands of documents that originated from IRA headquarters during the 1920s.
 
More than 90percent of the documents have never been to auction before.
 
The auction is being run jointly by Mealy's auctioneers in County Kilkenny and Adam's auctioneers in Dublin. The auctioneers expect the items to sell for over $700,000.
 
Barry wrote the letter to his friends while awaiting his execution on October 31st 1920.
 
The letter was written on two sheets of paper with a blue prison pencil and has a guide price of between $19,000 and $24,000.
 
“I have always considered myself lucky to have such a crowd of pals. It’s the only thing which makes it hard to go," writes Barry.
Other auction items include a bronze cap badge that Michael Collins wore when he was shot at Beal Na mBlath in Co Cork in 1922. The badge has a guide price of between $3,000 and $4,000.
 
A letter indicating that Collins was on a mission to Cork to propose a truce is also on sale with a guide price of between $4,000 and $5,000.
 
Some of the most historically significant documents on sale come from the archives of the former IRA chief of staff, Maurice Twomey, and are dated between 1926 and 1936.
 
The archives were found in a building in Dublin that was once the headquarters of the old IRA.
 
The auctioneers say the documents "will facilitate a new and authoritative approach to republican history in the period.”
 
The documents contain financial statements and details of arms deals around Europe.
 
There are 20 lots of IRA documents and each have a guide price of $13,500.
 
The auction takes place on Tuesday, April 20.