He holds a PhD in politics and is the author of six books, including a biography of John A Costello, The Reluctant Taoiseach, a two-volume biography of Éamon de Valera, Rise and Rule, and, most recently, From Crown to Harp: How the Anglo-Irish Treaty Was Undone.

Chairwoman of the Michael Collins Commemoration Committee, Grett O’Connor, which is organising the annual event on Sunday, August 23, at 3pm, said the committee was delighted that a figure of Mr McCullagh’s profile had accepted its invitation to speak at the ceremony.

“With his journalistic experience and extensive knowledge of Irish history, we know he will offer compelling insights into the life, work and legacy of Michael Collins,” Ms O’Connor said.

In previous years, speakers at the commemoration have mainly been politicians, including Taoiseach Micheál Martin and former tánaiste Leo Varadkar.

Mr McCullagh said he was honoured to be invited to speak at the annual Béal na Bláth commemoration.

“There are many different aspects to the life and career of Michael Collins: military organiser, intelligence chief, financial mastermind. But circumstances also turned him into a diplomat, a negotiator and a constitutional craftsman who played a key role, not just in the establishment of an independent Irish state, but in the evolution of Britain's Empire into a Commonwealth,” he said.

“As Ireland faces an increasingly turbulent international environment, it is timely to reflect on that legacy, and I am really looking forward to speaking at this year's commemoration,” Mr McCullagh added.