The mystery of the lost letters of Mary Stuart revealed

The mystery of the lost letters of Mary Stuart, Queen of Scots, who was executed by her cousin Elizabeth I at the end of a long religious dispute and struggle for the throne of England, has been revealed. The unpublished letters, 50 in all, were written in code between 1578 and 1584.They were found in the archives of the French National Library.

Now two cryptographers and a musician with the hobby of encryption have managed to read them. Published in the journal Cryptology, the discovery is considered the most important about the Queen of Scots of the last 100 years. Mary Stuart has gone down in history as one of the most unfortunate rulers of all time, victim of reversals of all kinds, as well as prisoner of her cousin Elizabeth I, then Queen of England, for about 20 years. Mary became Queen of Scots when she was just 6 days old, after the death of her 30-year-old father, and she was just 5 years old when she went to France, as she had already been betrothed as part of the complex network of arranged marriages among the major monarchies of the time.

She was Queen of France for a short time, but on the king's death she had to leave the country and was involved in the cruel struggle between Catholics and Protestants that involved the dynasties of Scotland and England. At just 19 years old, Mary was apprehended by her cousin Elizabeth I because she was considered a potential threat to her kingdom and was held captive for almost 20 years. From captivity Mary wrote hundreds of encrypted letters to her supporters and to the European chancelleries and, for these very letters, decrypted by one of the leading experts of the time, she was finally sentenced to death for treason: she was the first sovereign in modern history to be executed. Fifty hitherto unknown letters, found in the French National Library French archives, have now been deciphered. Most of these letters were addressed to Michel de Castelnau de Mauvissière, French ambassador to England, in which Mary repeatedly asked for greater support and complained about the conditions of imprisonment. In one of them she expresses anguish over the kidnapping of her son James, the future King James I.

"It is a truly exciting discovery," commented one of the three authors, George Lasry, a computer scientist and one of the coordinators of Decrypt, a project involving several European universities with the aim of mapping, digitizing, transcribing and deciphering as many encrypted historical materials as possible. These fifty new letters will shed light on some aspects of the imprisonment of which many details remain unclear: "This is the most important new find on Mary Queen of Scots for 100 years", commented John Guy, one of the leading experts on the history of the former sovereign of Scotland. Most of Mary's correspondence was encrypted with very advanced techniques, which had become very popular in those years and were considered practically inviolable. In his attempt to decipher Mary's letters, the scholar Thomas Phellipes developed and improved new techniques that not only made it possible to read the prisoner's missives and have her sentenced to death, but also revolutionized the entire field of cryptography. The new discoveries made by Phellipes made it necessary to find new and better techniques for encrypting secret messages.