The Irish Civil War: The Assassination of Sir Henry Wilson (Part 1)
Episode 580, The Rest Is History
Released on July 6, 2025

Introduction

In Episode 580 of The Rest Is History, hosts Tom Holland and Dominic Sandbrook delve into one of the pivotal events that ignited the Irish Civil War: the assassination of Sir Henry Wilson. Joined by historian Ronan McGreevey, the episode unpacks the intricate web of political tensions, personal vendettas, and strategic maneuvers that culminated in this dramatic turning point in Irish history.

Background on Sir Henry Wilson

Sir Henry Wilson was a towering figure in British military history. Born in Dublin in 1864, Wilson rose through the ranks to become the Chief of the Imperial General Staff. He played a crucial role in shaping British military strategy during the First World War, including the formulation of the joint strategy that led to the swift conclusion of the war in 1918. Reaching the rank of Field Marshal at a young age, Wilson was both respected for his military acumen and noted for his stern demeanor.

Notable Quote:
Dominic Sandbrook [07:11]: "He was the Chief of the Imperial General Staff and one of the people who put together the joint strategy that brought the war to an end in 100 days."

The Assassination of Sir Henry Wilson

On the fateful day of June 22, 1922, Sir Henry Wilson attended a war memorial ceremony at Liverpool Street Station in London. After the event, as Wilson returned to his residence at 36 Eaton Place in Belgravia, he was ambushed and shot six times by two veterans of his own army, Reggie Dunn and Joe O'Sullivan. This assassination sent shockwaves through both British and Irish political spheres, marking a significant escalation in the already volatile post-war environment.

Notable Quote:
Ronan McGreevey [16:12]: "They shoot him six times on the doorstep and then these two men run off."

Identity of the Perpetrators

Reggie Dunn and Joe O'Sullivan, the assassins, were not mere opportunists but deeply entrenched in the Irish nationalist movement. Both men were veterans of the British Army who, after experiencing the horrors of war, became disillusioned and turned to the Irish Republican Army (IRA). Their motivations were rooted in a fervent desire to see Ireland remain unified with Great Britain and a vehement opposition to the Anglo-Irish Treaty, which they perceived as a betrayal of Irish republican ideals.

Notable Quote:
Ronan McGreevey [19:50]: "It's about the ideal of Ireland represented by the Gaelic Revival."

Political Climate Leading to the Civil War

The assassination occurred against the backdrop of intense political strife following the signing of the Anglo-Irish Treaty in December 1921. The treaty, which ended the War of Independence, created the Irish Free State and partitioned Ireland, establishing Northern Ireland as a separate entity. While the treaty was widely supported in Britain, it was deeply divisive in Ireland, leading to a split within the nationalist movement between pro-treaty forces, led by Michael Collins, and anti-treaty factions who sought a fully independent Irish Republic without any allegiance to the British Crown.

Notable Quote:
Expert Guest [12:15]: "David Lloyd George sees this problem from the middle of 1920, that there’s going to have to be a political solution here."

Michael Collins' Role and Possible Involvement

A contentious theory discussed in the episode suggests that Michael Collins, a key architect of the treaty and leader of the pro-treaty forces, may have orchestrated Wilson's assassination to eliminate a vocal opponent of the treaty and to consolidate support for the pro-treaty side. This theory is supported by evidence presented in Ronan McGreevey's book, which posits that Collins saw Wilson's assassination as a necessary move to prevent further fragmentation of the newly established Irish state.

Notable Quote:
Expert Guest [39:18]: "Sam Maguire has sworn Reggie Dunn and Joel Sullivan into the IRB. And the head of the IRB, the one man who could sanction this attack to kill Henry Wilson is the president of the IRB, and that man is Michael Collins."

Aftermath of the Assassination

The murder of Sir Henry Wilson had immediate and far-reaching consequences. In Britain, the assassination was met with horror and a demand for swift justice, while the British government used the event to justify military action in Ireland. In Ireland, the assassination intensified existing divisions and provided a catalyst for the outbreak of the Civil War. The anti-treaty forces, already embittered by the treaty's terms, saw Wilson's death as a martyrdom that galvanized their cause against the pro-treaty government.

The Beginning of the Irish Civil War

Wilson's assassination directly influenced the escalating tensions that led to the Civil War. Faced with internal strife and external pressure, the pro-treaty government, under Michael Collins, issued an ultimatum demanding the removal of anti-treaty forces from key positions, notably the Four Courts in Dublin. When negotiations failed, the pro-treaty side initiated military action, marking the official start of the Civil War. This conflict would devastate Ireland, pitting neighbor against neighbor in a bitter struggle over the nation's future direction.

Notable Quote:
Dominic Sandbrook [44:17]: "Michael Collins, who according to your theory is actually the person behind the murder of Henry Wilson, to go in and attack these people who the British government are blaming for that assassination."

Conclusion

The assassination of Sir Henry Wilson was not an isolated act of violence but a pivotal event that encapsulated the deep-seated divisions within Irish society and the broader geopolitical tensions of the time. By removing a prominent pro-treaty figure, the path was cleared for the eruption of the Irish Civil War, a conflict that would shape the future of Ireland for decades to come. Episode 580 of The Rest Is History offers a comprehensive exploration of these events, shedding light on the complex interplay of personal motives and political imperatives that drove one of Ireland's most tumultuous periods.

Notable Moments Highlighted:

• [07:11] Discussion of Wilson's role in ending WWI.
• [16:12] Detailed account of Wilson's assassination.
• [19:50] Exploration of the assassins' motivations.
• [39:18] Theory linking Michael Collins to the assassination.
• [44:17] Initiation of military action leading to the Civil War.

For those eager to delve deeper into the unraveling of the Irish Civil War and the fate of Michael Collins, stay tuned for the next episode of The Rest Is History.