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Here is a list of past presentations at ICCH. The most recent presentation is at the top. Click on each listing to reveal more information below, including the speaker, presentation description and to access recordings.
Note: Effort has been made to ensure that the information on each presentation is accurate and up-to-date. To suggest a correction please contact the ICCH webmaster Patrick Hayes at .
In the 16th century, the popes needed to securely communicate with their nuncios, their permanent representatives in key European countries. They employed top-class cipher secretaries who designed codes that were the state-of-the-art of their time (together with those of the Republic of Venice). The most renowned cipher secretaries were Matteo Argenti and his nephew, who introduced innovative techniques to make codes highly secure and also wrote influential treatises of cryptography and cryptanalysis. Some of their codes are extremely challenging even today, despite the availability of modern computing. In this talk, George will give an overview of the history of the papal ciphers. He will describe how together with the DECRYPT project team, a large collection of ciphertexts from the 16th to the 18th century were digitized and transcribed in the DECODE database, and over 20 keys recovered with various techniques and the use of the CrypTool 2 platform (one of the ciphers is still unsolved). Based on this work, a picture emerges of a vibrant, innovative, and highly professional cipher organization in the 16th century, followed by a steady decline during the 17th and 18th centuries. A full analysis of the contents of the ciphertext material is still underway, some of the contents are interesting and reflect the popes' involvement in European politics, their struggle against Protestantism, and the nuncios' avid and constant need for more money.
February 6, 2021
Here is a list of past presentations at ICCH. The most recent presentation is at the top. Click on each listing to reveal more information below, including the speaker, as well as the presentation date and description. Presentation recordings are available separately, in the ICCH Portal.
To view upcoming ICCH presentations, click here.
Note: Effort has been made to ensure that the information on each presentation is accurate and up-to-date. To suggest a correction please contact the ICCH webmaster Patrick Hayes at info@cryptologichistory.org.
In the 16th century, the popes needed to securely communicate with their nuncios, their permanent representatives in key European countries. They employed top-class cipher secretaries who designed codes that were the state-of-the-art of their time (together with those of the Republic of Venice). The most renowned cipher secretaries were Matteo Argenti and his nephew, who introduced innovative techniques to make codes highly secure and also wrote influential treatises of cryptography and cryptanalysis. Some of their codes are extremely challenging even today, despite the availability of modern computing. In this talk, George will give an overview of the history of the papal ciphers. He will describe how together with the DECRYPT project team, a large collection of ciphertexts from the 16th to the 18th century were digitized and transcribed in the DECODE database, and over 20 keys recovered with various techniques and the use of the CrypTool 2 platform (one of the ciphers is still unsolved). Based on this work, a picture emerges of a vibrant, innovative, and highly professional cipher organization in the 16th century, followed by a steady decline during the 17th and 18th centuries. A full analysis of the contents of the ciphertext material is still underway, some of the contents are interesting and reflect the popes' involvement in European politics, their struggle against Protestantism, and the nuncios' avid and constant need for more money.
February 6, 2021
