The Role of Female Cryptanalysts from 1914 to 1946

This thesis shows that the history of cryptanalysis in Britain in the first half of the twentieth century has focussed on the contribution of men to the virtual exclusion of that of women, and produces evidence to prove that, from the First World War onwards, women, although in a minority, were working at the same level as their male counterparts, despite their lack of mention in the published literature which generally holds that only men worked as cryptanalysts during this period. The present research identifies that this was not the case, and that though the number of confirmed female cryptanalysts remains small and elusive, these women were nonetheless important for the role that they played. This thesis examines published work on British cryptanalysis between 1914 and 1946, demonstrating that these accounts are almost exclusively by men and about men. The research presented uses original documentation and interviews to advance and place on record knowledge about female cryptanalysts who worked in high-level codebreaking during time both of war and peace in a gendered approach. The analysis sets out the case studies of six women - four cryptanalysts, one linguist and a decoder - who typify the roles that women held in cryptanalysis between 1914 and 1946, providing an in-depth study of their backgrounds and roles they carried out for the British Admiralty’s Room 40, the War Office’s MI1(b) and HushWAACs, and the Foreign Office’s Government Code and Cypher School (GC&CS). The thesis provides a detailed historiographical chronology in a gendered approach of the women’s role in cryptanalysis from the beginnings of modern codebreaking in the First World War, through the interwar creation of GC&CS, to the vast cryptanalytical organisation at Bletchley Park during the Second World War, setting out the context of relevant literature and archival materials. Definitions are derived for key terms whose meanings have changed over the period, causing confusion and erroneous conclusions to be drawn, and key themes are identified which can be used in the identification of future female cryptanalysts. This thesis clearly identifies that women were working as high-grade cryptanalysts during the period 1914 to 1946, and offers pointers and analytical tools to potential further identifications in future research

On weak rotors, Latin squares, linear algebraic representations, invariant differentials and cryptanalysis of Enigma

Since the 1920s until today it was assumed that rotors in Enigma cipher machines do not have a particular weakness or structure. A curious situation compared to hundreds of papers about S-boxes and weak setup in block ciphers. In this paper we reflect on what is normal and what is not normal for a cipher machine rotor, with a reference point being a truly random permutation. Our research shows that most original wartime Enigma rotors ever made are not at all random permutations and conceal strong differential properties invariant by rotor rotation. We also exhibit linear/algebraic properties pertaining to the ring of integers modulo 26. Some rotors are imitating a certain construction of a perfect quasigroup which however only works when N is odd. Most other rotors are simply trying to approximate the ideal situation. To the best of our knowledge these facts are new and were not studied before 2020

The professionalization of cryptology in sixteenth century Venice

This article examines the evolution of cryptology as a business trait and a distinct, state-regulated and controlled profession in sixteenth century Venice. It begins by briefly discussing the systematic development of cryptology in the Renaissance. Following an examination of the amateur use of codes and ciphers by members of the Venetian merchant and ruling class, and subsequently by members of all layers of Venetian society, the article moves on to discuss the professionalization of cryptology in sixteenth century Venice. This was premised on specialist skills formation, a shared professional identity, and an emerging professional ethos. The article explores a potential link between the amateur use of cryptology, especially as it had been instigated by merchants in the form of merchant-style codes, and its professional use by the Venetian authorities, and it adds the profession of the cifrista – the professional cipher secretary – to the list of more “conventional” early modern professions

Fortuitous Endeavor—Intelligence and Deception in Operation TORCH

The Allied invasion of North Africa in November 1942 combined detailed planning, aggressive signals intelligence, deception, operational security, and good luck to achieve success seldom repeated—and that cannot be in the future if the episode’s lessons are not heeded

In a wilderness of mirrors: the ethics of translation in Cold-War espionage

The article looks at translation in the context of (counter)intelligence. Here translation finds itself in a situation in which scarcity of information turns originals into fragments rather than proper texts. This changes the way the translator works: s/he has to constantly justify his/her decisions, acting in several capacities or with different experts and foregrounding his/her presence in the text. This presence also points to the most difficult of ethical choices to be made. Translation mediates between conflicting or rivalling parties. To mediate, the translator must learn about and identify with an/the other, yet this other is an enemy.The translator must remember that s/he works not against but for the party to which s/he has pledged allegiance. The allegiance may be towards the party for which the translator works, or for the country in which s/he lives, and where s/he acts as a patriot. But the allegiance may be towards the ‘enemy’ – the absolute other – and here the translator’s loyalty is perceived simultaneously as treachery. The ethical ‘wilderness of mirrors’ to be navigated by translators within the (counter)espionage setting reveals a complex layering of multiple acts of fidelity and betrayal, agency and double agency