Never-before-seen documents, hand-written correspondence, photographs and stories feature in an exhibition that reveals the struggle between the IRA and British forces in a border county.
The Monaghan War of Independence files include more than 500 pages of first-hand accounts from Monaghan IRA veterans, which were gathered in the run up to the 50th anniversary of the Easter Rising in 1966.
The exhibition reveals the impact of the conflict on the local population, as well as sectarianism because of Monaghan's close proximity with the Unionist majority counties in Ulster, during the War of Independence.
Liam Bradley, curator of the Monaghan County Museum, said the county's population was 25% Protestant, which brought an extra element to the war.
He said: "It's a unique part of the story on the War of Independence in Monaghan, as the population of Protestants in the county, who were mostly unionists, felt in a way they were under threat from the IRA in their county.
"The Protestant population in Monaghan felt they needed to do something to protect themselves and this eventually led to the setting up of the Ulster Specialist Constabulary or as it became known the 'B Specials'.
"They were made up of local Protestant men and men from the northern part of Ulster.
"You can see how Monaghan became a focal point of what happened later on in the Troubles in that sense of Catholics and Protestants fighting each other and we wanted to tell that story about Monaghan.
"People were fighting for what they believed in, which was Monaghan remaining in the union and also Monaghan people fighting for it being part of the Republic.
"There was certainly a civil war going on within Monaghan.
"Protestants in Monaghan, Cavan and Donegal felt they were cut off after partition, they were on the wrong side of the line.
"While a large number of Protestant families left, some stayed and to this day you would have Protestant families here and only now some of them feel they are able to talk openly about their own family's history and what their family did."
The exhibition features original letters from Thomas Brennan, second in command of the 5th Northern Division of the IRA, as well as a collection of short films bringing eyewitness accounts to life.
It also includes IRA intelligence documents and training manuals, as well as a Monaghan Brigade letter-head.
"The letter-head is unique and rare, I've never seen those before," Mr Bradley added.
"You also have general orders instructing men not to speak to the enemy, telling them they are not to be seen talking to the RIC (Royal Irish Constabulary) and not to be seen talking to the Black and Tans and auxiliaries or there will be severe consequences.
"Other notes talk about what will happen if you are considered to be a spy, the penalties for that were usually always death so having that written down on letter form is really powerful.
"Religion really went hand-in-hand during this period. There were men who were devoutly Catholic and men who were devoutly Protestant but still involved in sectarian war."
The exhibition also tells the story about Monaghan man Eoin O'Duffy who went on to become IRA chief of staff.
O'Duffy was heavily involved in the GAA and used the club's structures to recruit men to join the IRA.
"During that period he is considered one of the top military commanders in the country and we felt it was important to tell his story," Mr Bradley added.
"O'Duffy's number two was Dan Hogan. His brother Michael Hogan was killed in Bloody Sunday in Croke Park."
Mr Bradley said the exhibition tells the story of both unionists and nationalists in the county.
"We felt a real sense that we could tell the story which is a real strength of museums. Museums are a safe place, not neutral but it engenders debate and tells a story of what happened," he added.
"Especially around cultural identity, what does it mean to be Irish, European, British, Northern Irish - museums can act as a catalyst for that discussion."