Samuel Pepys died (26-5-1703)

A naval administrator, best remembered for his diary (1660-1669).
"Though he had no maritime experience, Pepys rose to be the Chief Secretary to the Admiralty under both King Charles II and King James II through patronage, diligence, and his talent for administration."
https://en.wikipedia.org/wiki/Samuel_Pepys
I had the impression his diary was written in a cipher, but it was actually a form of shorthand called tachygraphy, invented by Thomas Shelton:
https://en.wikipedia.org/wiki/Thomas_Shelton_(stenographer)
The diary covers both his work and public life, and London life of that period, including the years of the Great Plague and the Great Fire, but also his domestic and personal affairs. In recounting his sexual adventures, he employs what Crystal calls "multilingual code-switching":
"she was to my thinking at this time une de plus pretty mohers that ever I did voir in my vida, and Godforgive me my mind did run sobre elle all the vestpre and night and la day suivants".