Thirty-six local IRA volunteers commanded by Tom Barry killed sixteen members of the Royal Irish Constabulary's Auxiliary Division.

The Auxiliaries and the previously introduced Black and Tans rapidly became highly unpopular in Ireland due to intimidation of the civilian population and arbitrary reprisals after IRA actions – including burnings of businesses and homes, beatings and killings.

[3] The Auxiliaries in Cork were based in the town of Macroom, and in November 1920 they carried out a number of raids on the villages in the surrounding area, including Dunmanway, Coppeen and Castletown-Kinneigh, to intimidate the local population away from supporting the IRA.

Barry scouted possible ambush sites with Volunteer Michael McCarthy on horseback and selected one on the Macroom–Dunmanway road, on the section between Kilmichael and Gleann, which the Auxiliaries coming out of Macroom used every day.

[6] As dusk fell between 4:05 and 4:20 pm on 28 November, the ambush took place on a road at Dus a' Bharraigh in the townland of Shanacashel, Kilmichael Parish, near Macroom.

Just before the Auxiliaries in two lorries came into view, two armed IRA volunteers, responding late to Barry's mobilisation order, drove unwittingly into the ambush position in a horse and side-car, almost shielding the British forces behind them.

The first Auxiliary lorry was persuaded to slow down by Barry standing on the road in plain sight in front of a concealed Command Post (with three riflemen).

A savage close-quarters fight ensued, between surviving Auxiliaries and a combination of IRA Section One and Barry's three person Command Post group.

The British claimed that the bodies of the dead "suffered terrible mutilation as though hacked with hatchets",[10] although Barry dismissed this report as atrocity propaganda.

They then reportedly opened fire again with revolvers when three IRA men emerged from cover, killing one volunteer instantly, Jim O'Sullivan, and mortally wounding Pat Deasy.

"[14]Some Bureau of Military History (BMH) accounts do not mention a false surrender, for example Section Three volunteer Ned Young's 1955 Witness Statement, published in 2003 (WS 1,402).

He recalled that when Section Two and the Command Post group engaged the second lorry that: "Tom Barry called on the enemy to surrender and some of them put up their hands, but when our party were moving onto the road, the Auxiliaries again opened fire.

Hennessy described in his BMH statement (WS 1,234) an incident in which, after Michael McCarthy was shot dead, he stood and shouted "hands up" to an auxiliary who had "thrown down his rifle".

IRA veterans reported variously that wounded Auxiliaries, finished off after the firefight, were killed with close range shots, blows from rifle butts and bayonet thrusts.

Ambush participant Jack O'Sullivan told historian Meda Ryan that, after he disarmed an Auxiliary, "He was walking him up the road as a prisoner when a shot dropped him at his feet".

Among the 16 British dead on the road at Kilmichael was Francis Crake, commander of the Auxiliaries in Macroom, probably killed at the start of the action by Barry's Mills bomb.

It is possible that the ongoing stress of being on the run and commander of the flying column, along with a poor diet as well as the intense combat at Kilmichael, contributed to his illness, diagnosed as heart displacement.

[26] The bodies of the killed Auxiliaries were sent to England after a lavish funeral procession through Cork on 2 December, which was provided with a military and police escort and attended by numerous prominent dignitaries from the British Army, Roman Catholic Church and Royal Irish Constabulary.

Local Coroner Dr Jeremiah Kelleher told the military Court of Inquiry at Macroom on 30 November 1920 that he carried out a "superfical examination" on the bodies.

[30] The principal published source for what happened at the Kilmichael Ambush is Tom Barry's Guerrilla Days in Ireland, which derided British accounts as atrocity propaganda.

The first account of a false surrender event at Kilmichael appeared in June 1921, seven months later, in the British Empire journal Round Table [31] by Lionel Curtis, citing a "trustworthy" source in the area.

[34] A 1924 letter to Free State Army headquarters concerning IRA casualty Michael McCarthy, released in 2021 by the Bureau of Military History, confirmed the contemporary perception of a false surrender.

The 26th November 1988 Southern Star subsequently referred to "The sole Survivor of the volunteers who performed so well under the leadership of general Tom Barry, namely Ned Young".

[43] Niall Meehan suggested in Troubled History (2008) and subsequently that Hart may have based his interview with the scout partly on Jack Hennessy's BMH testimony (reported above).

Examples of factual errors: stating falsely that the ambush was unplanned and a chance encounter; that two IRA volunteers had been mortally wounded and one killed outright, when the reverse was the case.

[54] Ryan's argument was queried by American historian W. H. Kautt, who discovered that the report had been included in a collection of captured IRA documents that was published by the British Army's Irish Command in June 1921 before the Truce.

She listened to Father John Chisholm's two veteran interviews for Liam Deasy's Toward Ireland Free, with Jack O'Sullivan and Ned Young (who also contributed a BMH account).

[59] She also stated that a December 1947 Kerryman newspaper account of the ambush by West Cork local historian Flor Crowley does not support Barry's Guerilla Days version of events.

Confirming Meehan's 2008 observation, Morrison noted that a quote Hart ascribed to the 'scout' was in fact uttered by Jack O'Sullivan, another interviewee, to Fr Chisholm.

John Young responded, "It was wrong of Dr Morrison to imply [...] that the late Jim O'Driscoll did not read my Affidavit before witnessing my signature.