1. Mary in prison

 

In 1586 Mary, Queen of Scots, was held prisoner under Sir Amias Paulet, a Protestant loyal to Elizabeth I. Mary’s contact with the outside world was limited to correspondence encrypted by her cipher secretary, Gilbert Curle, and smuggled out in casks of ale. Each letter was intercepted by a Catholic double agent, Gilbert Gifford, who joined Walsingham the year before.

 

Letters between Mary and her allies in England and abroad were deciphered and copied by Walsingham’s master forger and cipher secretary, Thomas Phelippes. Letters were then carefully re-sealed and sent on to their intended recipients, who carelessly continued with their scheme to establish Mary on the throne.

 

Different ciphers using unique combinations of symbols, letters, words and nulls were used for different recipients.