Agnes was a daughter of Landgrave
Maurice of Hesse-Kassel (1572-1632) from his second marriage to
Juliane of Nassau-Siegen (1587-1643), the daughter of Count
John VII of Nassau-Siegen. She was raised together with her siblings. She spoke six languages and composed music. On 18 May 1623 she married Prince
John Casimir of Anhalt-Dessau (1596-1660). During the
Thirty Years' War, she managed to soften the plight of Anhalt-Dessau by negotiating with the generals, both orally and in writing. She was considered a keen economist and mathematician. In 1645, she built a
fortified house in
Nischwitz, which was later developed into
Oranienbaum Castle. == Issue ==