Unmarked graves, 'killing fields' and political murders are terms we associate with the horrors of conflict in far-off places, but not our own country.
However, a controversial new book argues that during Ireland's short but savage War of Independence, and its immediate aftermath, some 50 people or more went missing in Cork city and county, executed by the IRA as 'spies' and 'informers', and their bodies dumped in the countryside.
In 'The Year of Disappearances', historian Gerard Murphy digs into a fiercely contested period of 20th-century Irish history to cast a light on atrocities committed in the extreme conditions of war.
This is an era and a topic that bitterly divides academics and historians, and Murphy acknowledges the trouble he had trying to verify what happened. His book started out as fiction based on accounts from local IRA men who had lived into the 1950s and 1960s.
The primary focus is on the actions of the Cork No 1 Brigade of the IRA, who were engaged in a dirty war of intelligence against British forces. The No 1 Brigade was initially led by Terence MacSwiney, the Lord Mayor of Cork who died on hunger strike in 1920.
MacSwiney was the one who designated an underground vault known as 'Sing Sing' in a local cemetery at Kilquane to be used as a holding pen for prisoners awaiting execution.
Prisoners were then moved to a stretch of isolated, hillside moorland and pine forest known as the Rea, between the parishes of Knockraha and Watergrasshill, some 10 miles outside Cork city.
Murphy calls this a "killing field", a burial ground for at least 20 victims of the conflict (one picture in the book depicts members of the Cork Volunteers enacting a 'mock' execution). The victims were a mixture of British soldiers, Black and Tans, and civilian 'spies', only three of whom are named.
A few key nationalist figures tower over this particular era. Sean O'Hegarty, a 40-year-old 'old-school' Fenian storekeeper from Douglas Road in Cork, replaced MacSwiney as head of the No 1 Brigade.
O'Hegarty was known for both his intelligence and the ruthlessness with which he oversaw his fiefdom. A major figure in the Cork IRA, he disliked people such as Michael Collins and Richard Mulcahy, deeming them too moderate in their approaches.
Meanwhile, Florence 'Florrie' O'Donoghue organised IRA intelligence in Cork city. It was in this role that he met his wife. Josephine Marchment Brown was the daughter of an RIC constable in Cork. She'd married a Welshman, who was later killed in the First World War, with whom she had two sons.
After moving back to Cork from Wales, Marchment Brown became embroiled in a custody battle with her Welsh in-laws, who wouldn't return her eldest son, Reggie.
Through a local priest, she was put in touch with O'Donoghue, who recruited her as a spy to pass on information about the British, on the basis of her army job in the Victoria Barracks. She agreed on condition the IRA get her son back, an operation that was approved by Michael Collins.
O'Donoghue and two others went to Wales, snatched the child and brought him back to Cork. He was kept in Youghal with Marchment Brown's sister for the remainder of the war. O'Donoghue and Marchment Brown then married in April 1921.
Another crucial protagonist in the affair is Martin Corry, later a Fianna Fail TD from 1927-1969. A popular, colourful politician, Corry lived until the age of 90, dying in 1979. He was known as an extremely anti-British republican and clashed with party leader éamon de Valera many times over this.
Corry was actively involved in the War of Independence, and although it's suggested that Corry may have over-stated his role in the freedom struggle, it seems most likely that he was involved in the killing of spies and informers. He is on record as once boasting: "British soldiers? I planted oats on British soldiers, and 'twas good oats!"
For his part, Corry claims to have disarmed and executed two British Army agents himself, as well as overseeing the deaths of other undercover agents, British soldiers, and deserters in the area.
One execution that has been authenticated was that of an RIC man called Williams for his part in the assassination of another lord mayor of the city, Tomás MacCurtain. Williams was court-martialled by the city brigade's top brass in Corry's own living room.
Corry also listed some 11 spies as having been killed in Knockraha area, including 'Paddy the Painter', who appears to have been a tramp. One historian has found at least 10 cases of tramps and tinkers being executed in the area.
During the conflict, Cork was "a city of spies", as labelled in an article in the ' London Times' in May 1921. Paranoia was rampant. 'Outsider' organisations such as the YMCA and the Freemasons were frequently targeted for ambush. The war in Cork, particularly the final six months before the truce in July 1921, was especially violent.
But even after the truce, the IRA continued to target what it deemed suspects. In the year prior to the start of the Irish civil war, the IRA was largely in control of Cork, attacking the remnants of British rule, resulting in peacetime killings.
On the night of April 26, 1922, an IRA member raiding the house of a Protestant loyalist family named Hornibrook was shot and killed by a member of the household, Captain Herbert Woods. The next day, Thomas Hornibrook, his son Sam and Capt Woods were taken and executed by the IRA. Their bodies were never recovered.
According to Murphy, over the next few nights, some 11 Protestants of all ages and occupations in Enniskeane, Ballineen and Dunmanway were taken from their beds and murdered. Some of the other victims, a family known as the Bradfields, had seen one of their relatives, a Methodist, murdered in 1921 for inadvertently telling IRA member Tom Barry (who was pretending to be a British soldier) that he was going to inform on the IRA to the British army.
West Cork Protestants started to flee the area in large numbers. Trainloads of 'refugees' passed through Cork city leaving for England on boats or mail trains. The killings were only halted on the orders of local IRA intelligence officer Sean Buckley, who attributed them to rogue IRA elements.
The motivations behind these Protestant killings cannot be stated with certainty. Were they sectarian, revenge killings, or carried out on the assumption of links to the Black and Tans, and Auxiliaries? The idea of native collaboration with British forces appears to be a sore spot that this country still isn't prepared to tackle.
While the idea of a deliberate campaign against Cork Protestants is disputed, statistics indicate that something was going on to cause an exodus. A comparison between the 1911 and 1926 census shows that the Protestant community declined by 50pc in Cork Borough and 40pc in the rest of the county. This compares with an average decline of 32.5pc across the 26 counties as a whole for the same period.
A cloak of silence fell over these killings once this savage era came to an end, though physical evidence has turned up since then. ESB workers laying electricity lines across the Rea in 1950s came across two uniformed bodies that had been thrown headfirst into a hole.
In 1963, a local farmer bought part of the Rea and discovered several skeletons. The remains were transferred to Watergrasshill garda station for reburial, and yet when a local woman later inquired about them, there was no record of it in the station's files.
Even more fascinating, Irish Free State forces exhumed a body from under the floorboards of Martin Corry's house in Sunville, Glounthaune, sometime during or after the Civil War. Indeed, a confidential dossier on Corry is held in the Department of Defence.
Getting to the truth of what happened gets more difficult with time. Murphy argues that in many cases, families never found out what happened to the 'disappeared', and even colluded in the silence out of fear of reprisal on other relatives.
What's more, it seems that after the establishment of the Irish Free State, the powers that be tried to start with a clean slate and forget the horrors.
Today, a small plaque in the Sing Sing vault commemorates nameless victims buried in the bogs. It may be the only official recognition these people will ever get.
'The Year of Disappearances: Political Killings in Cork, 1921-1922' is published by Gill & Macmillan