Rosa was the daughter of the apothecary Johann Georg Ritter and his wife Maria Magdalena Witz.
[1] William bought Rosa a property in Hanau and a country estate in the Rheingau and had her ennobled by the Holy Roman Emperor in Vienna.
On 17 March 1783, the Emperor elevated them to the nobility of the Empire with the Privilegium Denominandi.
In 1788, William hypocritically accused Rosa, who had been constantly pregnant with his children for most of the last decade, of infidelity and banished her to Babenhausen Castle.
Descendants from this marriage are said to live in the United States[citation needed].