The cryptography of the “maderistas” in the Mexican Revolution (1910-1911). Cryptanalysis of a cipher letter by Gabriel Leyva Solano

Abstract

This article is based on the text of a lecture that was delivered by the author in June 2010. It addresses issues related to the secret communications of the revolutionary movement led by Francisco I. Madero in 1910. It consists of two parts: the first is a brief critical review of a few cryptographic examples of the “maderista” movement that were generated between 1910 and 1911; the second part describes every step of the cryptanalysis applied by the author to decrypt a partially encrypted letter written by Gabriel Leyva Solano and addressed to Madero in 1910. In the end, the general purpose of this paper is to contribute to the knowledge of Mexican cryptography in the 20th century. In particular it seeks to make available to scholars the full content of the letter by Leyva Solano, for the first time after 100 years, and at the same time submit to technical and historical criticism the sort of cryptanalysis put into operation to recover the plaintext.