Général M. Givierge - Cours de cryptographie - 1932

Course in Cryptography, by General M. Givierge, 1932

The Course in Cryptography is the master work of General Marcel Givierge (Paris, July 27, 1871 – La Trimouille, Vienne, August 17, 1931), a polytechnic engineer, artillery officer, polyglot — notably fluent in English and Russian — and one of the most important French military cryptologists of his time. A graduate of the Superior War School, he was the originator of the creation of a permanent encryption section at the Ministry of War, which he helped establish in 1912 by leveraging his access to the minister Alexandre Millerand’s cabinet. From 1914 to 1917, he held the position of chief of the Cipher Section at the Grand Headquarters, a pivotal role in which he notably cracked the code of the German submarines. Clemenceau himself recognized in him a leading cryptologist.

The work presents itself as a methodical, instructional treatise covering all cryptographic techniques known at the time: substitution ciphers, transposition ciphers, permutation ciphers, periodic-key ciphers, double-key ciphers, frequency analysis, and decryption methods. It rests on extensive operational practice and draws the lessons of cryptology from the Great War, systematizing them within a rigorous framework accessible to officers without advanced mathematical training. It is directly in the lineage of Auguste Kerckhoffs’s Military Cryptography (1883), of which it constitutes the update and deepening for the era of mass communications and wireless telegraphy.

The historical importance of the Course in Cryptography extends far beyond the French context. In 1929, the Polish military intelligence services (Biuro Szyfrów) secretly organized at the University of Poznań a course in cryptology for mathematics students selected — including the future hero of Enigma cryptanalysis, Marian Rejewski. This course was, in Rejewski’s own words, “completely and literally” based on Givierge’s book. It was these Polish cryptologists trained on the Course in Cryptography who, in 1932, were the first to reconstruct mathematically the functioning of the Enigma machine — a breakthrough that Alan Turing and Bletchley Park would inherit directly, and which decisively contributed to the outcome of World War II.

The work was translated into English by the American War Department in 1934, under the title Course in Cryptography, attesting to its international influence. Today it remains an essential reference for the history of military cryptology in the interwar period.

1932, 304 pages, 15 x 23 cm. Worn cover. A stain on the front cover. No annotations."