Review of Code Breaker by Marc McMenamin (2018, Gill)

During the Second World War Ireland declared itself neutral and sought to stay out of the conflict. Its strategic location on the edge of the Atlantic and sharing a land border with Britain meant it was under pressure from both the Allies and Germany to favour and aid their cause. As McMenamin details, while the Irish government cooperated covertly with the British, especially on intelligence work and enabling flights over Donegal, it stuck rigidly to neutrality with Germany. The government maintained diplomatic relations and let its legation operate throughout the war, but also actively policed spying and jailed German spies, and sought to limit German influence on domestic politics and activities that might lead to the Allies to occupy the country. The IRA, on the other hand, hoped collaboration with Germany might lead to a united Ireland and the organization actively aided German spies sent to Ireland, notably Hermann Gortz. In response, section G2 of the Irish intelligence service sought to actively limit German communications and capture spies, and the Irish government interred IRA members. The Abwehr and SD sent a relatively small number of spies to Ireland including a handful of Irish nationals, a couple of South Africans, and an Indian. All but Gortz were caught shortly after landing or never made it ashore, and most seemed ill-suited to the task with the exception of Gortz and Gunther Schutz.

McMenamin provides a relatively broad account of Ireland’s relationship with Germany and Britain and its quest to remain neutral, focusing on the various spies Germany sent to Ireland and the work of G2. In particular, he spends some time detailing the work of Richard Hayes, the Director of the National Library, who was recruited on a part-time basis by G2 to crack German ciphers and help interrogate prisoners. Hayes was a polymath, skilled as both a linguist and a mathematician. His approach to cryptography was mathematical, but also social and technical, spending time talking to spies, riflling through their possessions for clues, and using forensics on burned paper. He made a number of contributions to cracking German ciphers including being the first to identify the use of microdots and solving agent in-field radio and legation ciphers, the latter of which were used in the Ardennes offensive. After the war his work was officially recognized in a secret meeting with Churchill and MI5, and he continued as director of the National Library until 1967 when he took up a position of librarian for the Chester Beatty Library.

While the book is nicely written and interesting, it’s timeline jumps around a bit, much of the material about German spies in Ireland has been told previously, and the new focus on Hayes is a little thin, in part due to the lack of source material. It would have also been nice to get more technical explanation of how the ciphers worked and were cracked, and the text linked to its sources. It would have also been preferable if the hyperbole could have been dropped. Hayes work was important, and his story worth telling, but he was not all that ‘stood between Ireland and Nazi Germany’ and ‘the fate of the country and the outcome of the war’ did not rest ‘on his shoulders’. His work was far from ‘crucial’ to the war (though it no doubt influenced Irish position and policy), and had marginal effect on turning the tide in the Allies favour (by late 1944 the tide had long turned). And some statements simply don’t stack up. Gortz was arrested in November 1941 and the idea he could have tipped the Germans to the double-cross system or the plans to land in Normandy as claimed make little sense. This hyperbole aside the book provides a readable overview of Ireland’s approach to Germany and its spies and the efforts of Richard Hayes and his G2 colleagues.