Some revolutionary figures arrive to us as portraits. Rory O’Connor arrives as an argument.

For a century he has been filed away under shorthand labels: anti-Treaty hardliner, Four Courts man, martyr, fanatic and tragic mistake. Gerard Shannon’s new biography Rory O’Connor: To Defend the Republic by Gerard Shannon (Merrion Press, February 2026) asks us to do something more difficult and more honest: meet the whole person, not just the ending. It is billed as the first biography of O’Connor and it lands at exactly the moment Ireland is still negotiating how to speak about the Irish Civil War without turning history into a loyalty test.

If you read Irish history, or argue about it, you already know why Rory O’Connor still matters. If you have never gone near the period because it feels like inherited rows and old bitterness, this is an excellent place to start. Shannon writes public history with pace and precision, but he is also interested in the human pressure points: loyalty, ideology, ego, fear, principle and miscalculation.

What makes Rory O’Connor so divisive

O’Connor was not a peripheral firebrand who wandered into the story late. He does not fit the easy stereotype of the revolutionary as pure romantic. He was Dublin-born, educated at St Mary’s and Clongowes and qualified in engineering at UCD before several years as a railway engineer in Canada. A UCD biographical note shows him moving through the pre-1916 networks around the Plunketts, involved in preparations and then caught in the post-Rising clampdown.

During the Irish War of Independence he held senior roles that make the later “just a symbol” version feel thin: director of engineering at Volunteer GHQ, involved in prison escapes in Ireland and Britain and appointed director of military operations in England in August 1920. That same UCD note credits him with coordinating arms conveyance and planning sabotage, including operations linked to the wider campaign in Britain. The Military Archives list him as Director of Engineering and Commandant General.

So when the Treaty split happens, what you are watching is not a hot take. It is a senior organiser making a very public stand. The UCD account captures the escalation and the unease: at a press conference in March 1922, he spoke about the power to prevent an election and, when asked about military dictatorship, replied: “You can take it that way if you like.”

That line is one reason readers keep rereading him in opposite ways. Was it bravado, warning, principle or menace? Shannon’s biography matters because it returns us to context: who O’Connor thought he was defending, what he thought was being lost and why he believed defiance could preserve legitimacy rather than destroy it.

The Four Courts and the point of no return

O’Connor is inseparable from the Four Courts occupation and the outbreak of the Irish Civil War. Two moments dominate his afterlife: the Four Courts and the Mountjoy executions.

In April 1922, O’Connor helped lead a force that occupied the Four Courts in defiance of the Provisional Government, with the hope of provoking a British response that might reunite the IRA against a common enemy. Read the communiqué he issued during the shelling and you can hear the mix of defiance and tragedy in real time: “The boys are glorious and will fight for the Republic to the end.”

Courts Service history notes that Michael Collins tried to persuade O’Connor and his men to leave, then ordered the Four Courts to be shelled on 28 June 1922. After days of fighting the garrison surrendered and O’Connor was arrested and held in Mountjoy.

For some, the occupation is remembered as a doomed gesture of republican purity. For others, it is remembered as a catastrophic miscalculation that forced a fragile state into war with itself. That is the debate, really: principle versus pragmatism and whether the Anglo-Irish Treaty was a staging post or a surrender.

The execution that still shocks

Then comes the moment that turns history into national scar tissue. On 8 December 1922, O’Connor was executed by firing squad alongside Liam Mellows, Joe McKelvey and Richard Barrett, in reprisal for the assassination of Free State TD Seán Hales. Writing in The Irish Times about the executions, Shannon argues that their enduring controversy lies in their dubious legality and the fact they were a reprisal for an act the four men were not involved in.

There is also the detail that stops you short. O’Connor was close friends with Kevin O’Higgins, even serving as best man at his wedding and O’Higgins later gave approval to O’Connor’s execution because he believed it necessary to secure the future of the state. If you want a single image of how the Civil War chewed through loyalties, that is it.

This is why Rory O’Connor remains an emotional figure. He sits at the point where friendship, ideology and state power collide, then still expects us to pick a side.

What Gerard Shannon brings, and why it matters now

Shannon, a public historian who specialises in the Irish revolutionary period, has form in writing these lives without flattening them into saints or villains. His first major biography, Liam Lynch: To Declare a Republic, was widely reviewed and made the non-fiction bestseller lists. An Irish Times review called it a “nuanced portrait” and praised its attention to the back and forth of decision-making. That approach is vital for Rory O’Connor, who has been claimed, condemned, mythologised and simplified for over a century.

The Irish Times also flagged Rory O’Connor: To Defend the Republic in its January 2026 roundup of notable nonfiction, emphasising its “first biography” status.

For readers, that combination matters: a subject who provokes instant certainty and a biographer with a track record of making certainty work harder.

Book launch at Chapters Bookstore, Parnell Street

We are delighted to host the launch of Rory O’Connor: To Defend the Republic at Chapters Bookstore, Parnell Street, Dublin 1 on Thursday 26 February, 6.30 pm to 8.30 pm (GMT). Historian Liz Gillis will MC and Éamon Ó Cuív will join as a special guest. Tickets are free via Eventbrite.

This is exactly the kind of evening Chapters loves: Irish history that is alive, contested and still relevant. Come early for a browse, pick up a new copy online at chaptersbookstore.com or do a rummage through our Irish history secondhand shelves in-store and bring your questions.

More by Gerard Shannon

If you want to read Shannon’s work in sequence, his Merrion Press listings currently include:

See you on Parnell Street on 26 February. Bring a friend and bring the uncomfortable questions. That is where Irish history begins to tell the truth.