Axel Oxenstjärna was the Lord High Chancellor of Sweden during king Gustavus Adolphus II, who fought in the 30-year war. Not exactly medieval, but fits the description otherwise.
This is very off-topic, but I cannot resist mentioning that when the ship was recovered from the bottom of the sea in 1961, one of the first things discovered from it was a miniature statue of Finnish olympic winner Paavo Nurmi. One of the best pranks by the student association of the Helsinki University of Technology. https://www.reddit.com/r/todayilearned/comments/62jm2z/til_i...
“Do you not know, my son, with how little prudence the world is ruled?”
Scandinavian nobility still used Latin commonly in those days.