A Rebel and a Traitor: A Fugitive, the Manhunt and the Birth of the IRA.

by Rory Carroll

From the master storyteller behind 2023’s critically acclaimed KILLING THATCHER

A Rebel and a Traitor is the story of a rogue imperial consul who sought to forge a new nation in the middle of a war – and the mercurial spy chief who sought to destroy him by any means.

The rogue consul was Sir Roger Casement, a decorated diplomat who turned his back on the British empire and instead joined the rising Irish cause at the turn of the 20th century. At the book’s centre is the manhunt for Casement led by intelligence officer Reginald ‘Blinker’ Hall, the legendary British spy chief who pioneered codebreaking, early mass surveillance and media manipulation.

As he did for the critically acclaimed Killing Thatcher, master storyteller Rory Carroll has combed diaries, letters, police reports, memoirs, court transcripts, secret service archives and declassified government files in the US, Britain, Ireland and Germany to create a page-turning history, and a story that still echoes through Anglo-Irish relations. A Rebel and a Traitor raises profound questions about honour, courage and the price of patriotism.

Genres: History, Nonfiction

416 pages, Kindle Edition

First published March 26, 2026

About the author

Rory Carroll (b. 1972) is a journalist who started his career in Northern Ireland. As a foreign correspondent for the Guardian, he reported from the Balkans, Afghanistan, Iraq, Africa, Latin American, and the United States. His first book, Comandante: Hugo Chavez’s Venezuela, was named an Economist Book of the Year and BBC Radio 4 Book of the Week. He is now based in his native Dublin as the Guardian’s Ireland correspondent.

Reviews

[Selena · Rating 5 out of 5]

The book starts with 3 men leaving a German sub in the dead of night for the southwest coast of Ireland, mid-way through WWI. A group of men prepared to die for their country, but that country is Ireland, not England. One of them is Sir Roger Casement - respected British diplomat with a strong humanitarian record overseas. But also a vocal advocate for Home Rule, devolved government in Ireland. This is the story of how an Irishman came to work for the British government, be knighted for his service, and then collude with Germany in his efforts to initiate revolution in Ireland. But Carroll superbly weaves this together with the emergence of spying and the secret service being used to great effect in wartime, society attitudes to homosexuality, the roots and events of the Easter uprising in 1916, and the seeds of the IRA.

It did take me longer to get into this book than with the author’s brilliant Killing Thatcher, I think, because I didn’t know anything about the characters involved here. But Carroll brilliantly brings them to life. (NB. My proof copy was missing maps and photographs, which I understand the final version includes - I would definitely have referred to these.) There are tragic mistakes and choices, unwavering belief, heartbreaking love stories and an epic battle of wits in the dogged, relentless manhunt for Casement, using some controversial tactics. Carroll has written another well-researched account: history in the guise of breathtaking storytelling.

[Martin Paul · Rating 4 out of 5]

An evocative and moving story.

"A Rebel and a Traitor" opens in London in 1914. Roger Casement is set to address the Royal Commission. He is a renowned and respected diplomat and advocate for Irish home rule, but unknown to most, he is also instrumental is arming the cause, and has few qualms about what independence will cost.

The story of Casement, his past, and leading up to his fall is told in minute detail - his early days in Africa, the Congo and south America are all covered, his growing fame as a diplomat, and then his collaboration with Germany to arm the Irish are full of colourful detail and context. At the book’s centre is the hunt for Casement by intelligence officer Reginald Hall, a legendary British spy chief who pioneered codebreaking, mass surveillance and media manipulation. The story is replete with characters who assisted both Casement and Hall, and the part they played in his life.

The research that author Rory Carroll must have carried out is remarkable - he cites diaries (including Casement's own), letters, police reports, court transcripts, secret service archives and government files from the US, Britain, Ireland and Germany. In other hands this book could have been a dry re-telling of a story overlooked nowadays. Instead it reads like a thriller from Frederick Forsyth or Len Deighton.

The book is replate with photographs of Casement and many other key figures, and features a detailed chapter by chapter bibliography and notes. Highly recommended.

[Kim · Rating 5 out of 5]

2026 has been the year of non-fiction books for me. I spent much time in World War II as written by Ben McIntyre and Jonathan Freedland and relished the opportunity to read an equally powerful account of events in and around Ireland at the time of World War I. A Rebel and a Traitor gave amazing insight into the struggles of Ireland to become independent from Great Britain. Specifically focusing on Sir Roger Casement, quite the enigma for a British diplomat, and the Navy man turned intelligence officer hunting him, Reginald ‘Blinker’ Hall.

In true cat and mouse fashion, this was a gripping back-and-forth spanning the globe from America to Germany. The Irish rising is a topic I knew little about and found the thoughtful, balanced assessment of the time and the men working toward Irish independence enthralling. Rory Carroll brought all the key figures to life with true enthusiasm easy to discern as a reader. So well researched, I couldn't put it down. The details and facts liberally woven throughout gave a true feel for the time and events as they occurred.

Though the cover says it is the birth of the IRA, to me it is more about the tactics used by the Irish early on that were then employed and expanded to cruel effect later during the troubles in Northern Ireland. This isn't specifically about the IRA though I am curious to read Carroll's Killing Thatcher as it is well regarded.

If you are on the hunt for compelling non-fiction you surely found it here in A Rebel and a Traitor. I highly recommend.

[Libby Chapman · Rating 4 out of 5]

Author Rory Carroll has combed through countless primary sources to create a fascinating timeline of the Roger Casement's final years. The author has produced a gripping historical picture of a man whose myth has become conflated with the prevailing views of homosexuality that existed in the early twentieth century.

T.E. Lawrence (Lawrence of Arabia) intended to write his own biography of Roger Casement, hoping that "his enemies would think I was with them till they had finished reading it and rose from my book to call him a hero. He had the appeal of a broken archangel."

A Rebel and a Traitor also highlights the story of those who sought Casement's capture, providing an enlightening picture of the development of British spy craft during the First World War.

Essentially an idealist, Roger Casement saw himself very much as a rebel and not a traitor. Rory Carroll tells this complicated and very human story with nuance and sensitivity.

As a Bookseller I would highly recommend this book to those who have an interests in Irish, British and European history, spy craft, and LGBTQ+ issues.

Many thanks to the book's publishers for providing a proof copy of this book for an impartial review.

[Julie Hudson · Rating 3 out of 5]

Thank you to LibroFM, Mudlark and Harper Collins for the ARC and ALC.

Let me start by saying Killing Thatcher is in my personal top ten ever and my continual handselling of this book to customers in the bookshop has led to it being in the top 5 of our best selling history books.

I was therefore very excited to read this by Rory Carroll. Because of lack of time I ended up listening to it rather than reading it and may have rated it higher had I read it. Unfortunately the subject matter didn't grip me in quite the same way and I found myself drifting in and out and not completely engrossed.

It's the story of the incorrigible Sir Roger Casement - a gentleman completely committed to the cause of indiginous people around the world and Irish Home Rule who tried to get Germany to support the Irish cause with weapons around the time of first world war. Casement was also a homosexual who was double crossed by his Norwegian mercenary lover and oddly kept very intimate diaries of his sexual encounters that would be discovered and used against him.

[Varun Bhakay · Rating 4 out of 5]

A gripping account with a somewhat misleading subtitle (the IRA is really not central to the narrative in any way), Rory Carroll exhibits once again his storytelling muscle, albeit with a greater editorial slant than was visible in "Killing Thatcher". The details are confounding, the characters a real interesting lot, and the way they come together integral to forming our understanding of Britain at the cusp of something quite unique and unforeseen till the dust had settled after the events of Easter Monday 1916.

Carroll is at his best when dealing with the complex, overwrought Sir Roger Casement, and slightly less enjoyable as a writer when dealing with the man tracking Casement - Capt Reginald Hall RN. Between the two of them, and the men and women in between, the story of Casement's role in the struggle for Irish independence is a compelling one, and Carroll does it justice.

[Greville Waterman · Rating 5 out of 5]

This was a wonderfully researched, objective, thorough and highly readable account of the life and death of Sir Roger Casement who transmogrified from a British diplomat and hero to a traitor for his leadership role in Irish nationalism.

His Irish background is thoroughly explored as well as the political sensitivities of the time. All sides of the argument are explored and thoroughly explained as well as there being a fascinating insight into the taboo subject of homosexuality on Edwardian Britain and the development of spy catching and the secret service in England.

A fascinating and enlightening read.

[Rachel N · Rating 4 out of 5]

A highly readable account of the life and death of Sir Roger Casement, a subject I knew nothing about but found fascinating. The story of Casement’s life is complex, covering his work as a British diplomat, his later role in Irish nationalism, his homosexuality in Edwardian Britain, the hunt for him by intelligence officer Reginald Hall and the work of the spy services, but it's all beautifully balanced. The whole book is based on very detailed research from a wide range of sources, but the author never lets that weigh down a very fast paced and well balanced story.

Thanks to Netgalley and the publisher for an advance copy in return for an honest review.

[Stephen · Rating 4 out of 5]

thanks to the publishers and netgalley for a free copy in return for an open and honest review

Interesting book about the latter part of Roger Casement's life and his journey to Germany to help Irelands cause against Britain and the lead up to his change from loyal servant to rebel. the author examines the motives of his change and events leading up to the 1916 easter rising and the hunt by intelligent forces against him.