Editor’s Introduction: The DMNES staff are super delighted to host a three-part guest blog by Dr. Anna Dorofeeva. Dr. Dorofeeva is a historian specialising in Western Latin book history and culture, and her current work focuses on ciphers and cryptography in medieval manuscripts; you can follow her on Twitter at @LitteraCarolina. In this series of posts, she talks about how personal names were rendered in code form in the Middle Ages.
Secret names: What’s in a name? (Part 2)
Dr. Anna Dorofeeva, ZKS Barker Junior Research Fellow, Durham University
Not all monks were quiet or modest! In this manuscript from France, containing some works by St Jerome and dated to 806 CE, the scribe Agambertus covered an entire page in ciphers.
The first is a monogram, a series of letters joined together and spelling out the name of the woman who commissioned the manuscript: Hlottildis or Theodildis (since the final S is missing, this interpretation is uncertain). The monogram also contains the abbreviation ‘abbat.’ for ‘abbatissa’, meaning ‘abbess’, indicating that Agambertus’ commissioner was fairly powerful.
The second code is Agambertus’s name and an invocation, all written in Greek letters mixed in with a made-up alphabet (known as the alphabet of Aethicus Ister) and ‘Marcomannic’ runes.
After that, there is a plaintext referring to the sixth year of Charlemagne’s imperial reign, followed by a request to the reader to pray for the scribe, written by replacing each vowel with the following consonant.
The lower part of the page is filled with palindromes: three squares playing around with the words SATOR, AMOR, and AMEN; and two anagrams of the scribe’s name, one of which is arranged in the form of a cross. 
Agambertus evidently enjoyed experimenting with ciphers, which enabled him to show off his skill as a scribe. This page of puzzles would have intrigued its readers in the ninth century, as it does today, but it was also a more serious sign of a belief in the written word as the Word of God. This was reflected in human language and in the stories of the Bible, but it needed decoding and interpreting before it could be truly understood.
Agambertus wasn’t the only one who enjoyed visual puzzles. Monograms and monogrammatic writing, in which letters nestle within or on top of each other, were especially popular in the early Middle Ages. In this book, made in ninth-century France, the scribe Audgarius first wrote the title of the legal text he was copying. At the bottom, he added his own name and the Latin word ‘nomen’, ‘name’, as if they were also part of the title – but in a much more complicated arrangement on top of each other.
 I. Garipzanov, Graphic Signs of Authority in Late Antiquity and the Early Middle Ages, 300–900 (Oxford, 2018), pp. 260–62.