Pearse happened to share his name with the figure-head of the Easter Rising six years earlier — but his mother was also named Margaret, and he had a younger brother Willie, just like Wilie Pearse who was also executed in May 1916.

The new claim emerges in files just made available to researchers about the deaths of Pearse, Daniel O’Sullivan and Michael Hayes outside Upton on October 4, 1922.

Tom Barry and Tom Hales claimed over a decade later that a Fr O’Connell led the National Army party that killed the three. Barry named him as “ex-Father Jeff O’Connell”, and said he was told “that this Fr O’Connell actually did the shooting.”

He appears to be referring to Jephson O’Connell, who signed up to the National Army at Kinsale six weeks earlier, on August 21. It was the day after National Army forces landed in Kinsale and anti-Treaty IRA evacuated the town. The fledgling Free State saw an influx of army recruits after taking over Cork City earlier in August.

The day after O’Connell joined the army, its commander-in-chief Michael Collins was killed elsewhere in Co Cork at Béal na Bláth.

The 35-year-old was a commandant in the infantry by November 1922, and gave his next-of-kin as a Catholic curate in Kinsale, Fr E Fitzgerald, who he said was his cousin. Curiously, however, O’Connell gave his own home address as care-of the Guaranty Trust at Pall Mall in London, in a National Army census.

Tom Barry, seen here speaking at Kilmichael in 1969, claimed that Daniel O’Sullivan, Patrick Pearse, and Michael Hayes were killed by a Fr Jeff O’Connell of the National Army in a Cork Civil War incident in 1922.

He is almost certainly the same Jephson O’Connell who outlined concerns about army discipline in a series of secret meetings that began around September 1922 with Kevin O’Higgins, minister for justice in the first Free State government. These meetings influenced actions by O’Higgins around an army mutiny in 1924 that led to the resignation of Defence Minister Richard Mulcahy.

A separate account held in the National Library of Ireland, written by a former National Army figure, suggests Jephson O’Connell was an ex-chaplain to the British Army. It said he had rendered spiritual assistance to IRA members in West Cork during the War of Independence, including Tom Barry’s Flying Column.

This could be a confusion with Canon Patrick O’Connell of Enniskeane, an older priest who heard confessions of Barry’s men before the Kilmichael ambush in November 1920. However, the same account goes on to say the same Jephson O’Connell was defrocked after defying orders of Cork’s Catholic Bishop Daniel Coholan to cease his activities with the IRA.

This tallies with an account by Cork Fianna Fáil TD Sean MacCarthy in Patrick Pearse’s file, when he wrote to party colleague and Defence Minister Kevin Boland in 1957.

The grave in Kinsale of Patrick Pearse and Daniel O’Sullivan, killed in 1922. Picture: Military Service Pensions Collection, Military Archives

“I could use a far stronger word than ‘killed’,” he wrote about the death of Pearse and his fellow anti-Treaty IRA fighters.

““Father?” O’Connell, afterwards ‘silenced’ by the Bishop of Cork; and supposed to be ‘silent’ in the Civil Service (Dept. of Defence) but really most active behind the scenes, and not in our interests,” MacCarthy wrote in a letter revealed in the latest release last week from the Military Service Pensions Collection (MSPC) by the Department of Defence and Defence Forces’ Military Archives.

In his April 1933 account of the deaths at Upton in October 1922, also contained in one of several MSPC files relating to Patrick Pearse, Tom Barry wrote that he “was murdered by members of “National Army.””

“The particulars of this Volunteer’s death are well known to ex-Father Jeff O’Connell who whilst acting as Chaplain in Kinsale left the Barracks (carrying a rifle and two revolvers) in charge of a raiding party of Free State troops,” he wrote.

His reply to a query from the Military Service Registration Board said that they “murdered several Republicans” in the same raid.

“I was told that this Fr O’Connell actually did the shooting. This ex-priest is now I understand a high official in the Free State Land Commission. I suggest that a statement can be got from him as to the murders — especially as he is now a paid State official.”

In a separate handwritten form, completed on the same date, Tom Hales who previously commanded the IRA’s Bandon Battalion, wrote: “Free State soldiers from Kinsale under command of Rev O’Connell and Capt Byrne were or must have taken up positions, creating an element of surprise, against Republicans in this area.

“When this became known to Republican [Officer-in-Command], Pearse and his two comrades was [sic] placed in a position by Tom Kelleher O.C, the safest and best, as he thought. A few minutes after, shots rang out. No other engagement ensued. The three were found dead,” wrote Hales.

In his own account a few months later, in support of a claim by Patrick Pearse’s mother Margaret, Tom Kelleher said he was in charge of the IRA column, but made no mention of who fired the fatal shots.

“He was ambushed by the Free State Army, while going on outpost duty, and shot dead... A rifle bullet went through his chest and out his back at the shoulder blade,” Kelleher wrote.

The bodies were found by a sister of Sean MacCarthy, the TD who wrote to Kevin Boland in 1957, half a mile from the family home.

The same allegation of involvement by a priest in the death of IRA figures in the Civil War was made in an interview given to IRA commander Ernie O’Malley in one of his interviews with IRA veterans carried out decades later. However, Jack Fitzgerald from Kilbrittain near Kinsale, gave a different name.

“Jeff..O’Connor, a priest, shot some of the lads and he is now in the Department of Defence,” he told O’Malley.

The National Army’s official account of what happened at Lisaniskey near Upton was carried in the Cork Examiner on October 10. It said three IRA men were shot dead after refusing to halt when they attempted to cut off National Army troops of the Kinsale command operating in the Upton area.

Further National Army reports, copied in an MSPC file relating to Daniel O’Sullilvan, reveal that a document captured the day before tipped off the National Army to a meeting of IRA Kinsale battalion officers in the area that evening.

On the same day the newspaper report apeared, the IRA’s west Cork Brigade paid the full funeral £43 expenses of the three men killed at Upton, including more than £10 for wreaths, according to a National Army report.

Daniel O’Sullivan’s file includes a letter from his former employer David Acton, a Kinsale merchant for whom he worked as a labourer for about four years up to shortly before his death.

According to Philip O’Neill from Kinsale, writing to Defence Minister Frank Aiken in 1934, the O’Sullivan family were “earnest workers in the Irish-Ireland movement”.

“Young Dan gave sincere proof of his loyalty to the Republican cause by going out with a Column after the evacuation of Kinsale by the Republican forces,” he wrote.

The dead IRA man’s 83-year-old father Patrick was awarded a £75 gratuity payment by Mr Aiken in 1934, on the recommendation of the Army Pensions Board.

A similar claim by Patrick Pearse’s father Batt was unsuccessful, although his mother Margaret received a gratuity of £112 and 10 shillings, as she had proved herself to have been partially dependant. The couple had separated around 1910 when Patrick was 13 and he and most of his siblings stayed with their mother, one brother going on to join the British Army.

Patrick Pearse was casually employed as a labourer with a contractor at the British Army barracks in Kinsale and at Charles Fort, also in Kinsale up to August 1919. He was more permanently employed up to his arrest in February 1921, earning over £2 a week.

Writing to the Department of Defence in November 1933, Batt Pearse described himself as as “a Bitterly Disappointed Father of Patriot” and requested the return of the brith certificates and death certificate sent in support of his claim.

“They cost me 12 shillings which I could ill afford to pay,” he wrote.

Patrick Pearse’s sister Annie Pearse was awarded a dependant’s allowance worth £125 a year from September 1957 up to her death in 1988.

Michael Hayes was an 19-year-old apprentice carriage painter in Bandon, one of five orphaned children who lived with an aunt and uncle. He was a member of the republican boy scouts, Na Fianna Éireann, and an IRA scout during the War of Indpendence from about 1919, and was present when the IRA kidnapped the Earl of Bandon shortly before the Truce of July 1921.

During the Civil War, he operated with the Ballinspittle IRA company from the Kinsale area, but also fought with Cork anti-Treaty forces in Co Limerick.

Claims for his siblings under military service pensions laws were unsuccessful in the 1930s and 1950s.