In later life, he served as Resident Ambassador of the English Crown in the Holy Roman Empire,[1] and was head magistrate for two districts of the Electoral Palatinate.
William Curtius worked as secretary and diplomat during the Thirty Years' War, promoting the cause of the Palatinate and the restoration of the fortunes of the heirs of the House of Stuart.
While based with the exiled Palatinate and English courts in The Hague, Curtius also became a financier, part of raising the extraordinary loans and cash payments that paid for the armies fighting across Europe.
He married into a network of Dutch and Huguenot merchants and bankers, with strong connections to the French court and to the mayoralty of the city of Frankfurt.
His support for the Stuarts was rewarded with a Baronetcy of England, a formal role as Britain's ambassador to the Holy Roman Empire, and membership of the Royal Society.
A multi-lingual German diplomat based in The Hague, representing royal families and the interests of the Palatinate through decades of civil and inter-state wars, intrigues and religious strife, appears to have been too complicated and possibly too European to be well-remembered in any one country.
William Sr. father Michael Curtius and his wife Ursula Cruzia probably came from the area around Geneva (ex Allobrogibus) and probably led their ancestors to the Lombard noble family of the Curti di Gravedona.
[7][8][9] On seeing his son's above-average talent, Curtius' father sent him to prepare for university studies in the Calvinist Collegium Casimirianum in Neustadt an der Haardt.
Curtius launched his diplomatic career as a secretary to Frederick in 1629, possibly on the recommendation of his friend Joachim, son of the Palatinate administrator Ludwig Camerarius.
[1] It was in this English role that he was one of the last people to meet with the Elector Palatine in November 1632, when Frederick was already displaying early symptoms of the plague that killed him only days later.
Elizabeth Stuart wrote to diplomat Sir William Boswell in his support, I pray remember what I saide to you about Curtius that if the king my deare Brother will not keep him in his service, he may be dismissed with his favour, and the sooner the better for the poore man is there [in London] on his own purse and cannot be paid what is owing of him.
Late in the year, he returned to Elizabeth's exiled court at The Hague, having failed to secure material English support for the Palatinate cause.
[1] In 1652, when he was appointed to the Baronetcy by the then-exiled Charles II, Curtius was "resident for his majesty, with Gustavus, King of Sweden, and the princes of Germany".
[28] "Mr Oldenburg read a Latin letter to himself from Sir William Curtius dated at Umbstad December 2, 1668 containing assurances of his willingnese to send what philosophical communications he could out of Germany and particularly from the Elector of Mentz and from the physician of the Landgrave of Hesse Darmstadt.
After Catharina's death in childbirth in 1659, Curtius married the widow of the mayor of Frankfurt, Anna Sibylla von Stalburg, who was born to a Viennese banking family.
[31] In the novel Quicksilver, Neal Stephenson quotes from The History of the Royal Society of London,[32] in which "the president produced from Sir William Curtius a hairy ball found in the belly of a cow".