Princess of Anhalt-Dessau, daughter of Leopold II Maximillian of Anhalt-Dessau (1700-1751) and Giesela Agnes of Anhalt-Köthen (1721-1751). In 1769, she moved to Herford Abbey where she became Dean.
She married Johann Just, Freiherr von Löen (1737-1803) and Lord of Cappeln and Tecklenburg in 1779, and had at least three children, Agnes Leopoldine Casimire (named after herself and her two favourite sisters, who were by then both deceased)1 and Friedrich2.
Boswell was introduced to Princess Agnes (as she was commonly known) at the court of Dessau on September 24, 1764. He danced with her, and with her two sisters, at a ball on September 29, held by the Princess Wilhelmine in honour of the deposed Duke of Courland.
On September 30, 1764 - the day of his taking leave of Dessau - he described the Princess as "a comely, black, amiable young lady."