Back in 2018, I reported codebreaking of Catherine of Aragon's letter to King Ferdinand, her father from November 1509. It was achieved by Victor and Thomas Bosbach independently. At the time, I refrained from disclosing the solution because I had submitted it as a challenge to the public at MTC. Although my contact at MTC3 gave me an ok for publishing the results as early as 22 September 2020, I couldn't reconcile the two similar but different solutions to derive the best deciphered text. Now I publish the results, hoping that someone versed in Spanish completes the solution, and, better still, contextualizes the deciphered text.
See: Solution of Ciphertext of Catherine of Aragon to King Ferdinand (1509),
