The timing of the execution, only seven days after the death by hunger strike of Terence MacSwiney, the republican Lord Mayor of Cork, brought public opinion to a fever-pitch.

His pending death sentence attracted international attention, and attempts were made by U.S. and Vatican officials to secure a reprieve.

His father, Thomas Barry Sr., ran a prosperous dairy business in Dublin based at Fleet Street and supported by the output of the family's farm at Tombeagh, Hacketstown, County Carlow.

In 1915 he was sent to live in Dublin and attended the O'Connell Schools for three months, before enrolling in the Preparatory Grade at St Mary's College, Rathmines, in September 1915.

These events served to incite his nascent nationalism to the extent that he expressed his desire to join Constance Markievicz's Fianna Éireann.

[19] The following year, at age 16, he was introduced by Seán O'Neill and Bob O'Flanagan to the Clarke Luby Club of the Irish Republican Brotherhood (IRB).

[24] Barry's one significant action prior to Monk's Bakery was the raid for weapons on a military outpost at King's Inn on Constitution Hill.

On 1 June 1920, a hand-picked team from the Dublin Brigade's three battalions attacked the site taking the 25 soldiers by surprise and seizing the available weapons.

Within only six minutes the raiders had secured rifles, light machine guns, and large quantities of ammunition, and had departed the site with no casualties.

Douglas informed him that he and John Joe Carroll of H Company had noticed that a British army lorry guarded by an armed party of soldiers made twice weekly trips to Monk's Bakery at 79-80 Church Street to obtain bread.

[27] After obtaining permission to conduct the ambush Captain Kavanagh selected men from his company to participate and developed his detailed plan.

[27] On Sunday night, 19 September, Kavanagh assembled his men and told them to report to the O'Flanagan Sinn Féin Club at 9:00 a.m. the following morning.

Macready informed General Sir Henry Wilson on the day that sentence was pronounced "of the three men who were killed by him (Barry) and his friends two were 19 and one 20 — official age so probably they were younger... so if you want propaganda there you are.

Nationalist Ireland had decided that men like Kevin Barry fought to free their country, while British soldiers — young or not — sought to withhold that freedom.

Barry received orders on 28 October from his brigade commander, Richard McKee, "to make a sworn affidavit concerning his torture in the North Dublin Union."

Arrangements were made to deliver this through Barry's sister, Kathy, to Desmond Fitzgerald, director of publicity for Sinn Féin, "with the object of having it published in the World press, and particularly in the English papers, on Saturday 30th October.

[32]On 28 October, the Irish Bulletin, the official propaganda news-sheet produced by Dáil Éireann's Department of Publicity,[33] published Barry's statement alleging torture.

[citation needed] Historian John Ainsworth, author of Kevin Barry, the Incident at Monk's bakery and the Making of an Irish Republican Legend, pointed out that Barry had been captured by the British not as a uniformed soldier but disguised as a civilian and in possession of flat-nosed "Dum-dum" bullets, which expand upon impact, maximising the amount of damage done to the "unfortunate individual" targeted, in contravention of the Hague Convention of 1899.

[31] Erskine Childers addressed the question of political status in a letter to the press on 29 October, which was published the day after Barry's execution.

[28] In a letter addressed to "the civilised nations of the world", Arthur Griffith — then acting President of the Republic wrote: Under similar circumstances a body of Irish Volunteers captured on June 1 of the present year a party of 25 English military who were on duty at the King's Inns, Dublin.

General Sir Nevil Macready, Commander-in-Chief of British forces in Ireland then nominated a court of nine officers under Brigadier-General Onslow.

He was returned to Mountjoy, and at about 8 o’clock that night, the district court-martial officer entered his cell and read out the sentence: death by hanging.

The Barry family recorded that they were upset by this encounter because they considered the chief chaplain "the nearest thing to a friend that Kevin would see before his death, and he seemed so alien.

Dublin Corporation met on the Monday, passed a vote of sympathy with the Barry family, and adjourned the meeting as a mark of respect.

[35] On 14 October 2001, the remains of these ten men were given a state funeral and moved from Mountjoy Prison to be re-interred at Glasnevin Cemetery in Dublin.

MacGreevy had unsuccessfully petitioned the Provost of Trinity College Dublin, John Henry Bernard, to make representations on Barry's behalf.

In 1934, a large stained-glass window commemorating Barry was unveiled in Earlsfort Terrace, then the principal campus of University College Dublin.

In 2007, UCD completed its relocation to the Belfield campus some four miles away and a fund was collected by graduates to defray the cost (estimated at close to €250,000) of restoring and moving the window to this new location.

The ballad "Kevin Barry", relating the story of his execution, has been sung by artists such as Paul Robeson,[43] Leonard Cohen,[44] Lonnie Donegan, Stompin' Tom Connors,[45] the Hootenanny Singers, Damien Dempsey, The Clancy Brothers, Tommy Makem and The Dubliners.

[citation needed] At the place where Kevin Barry was captured (North King Street/Church Street, Dublin), there are two blocks of flats named after him.