Catherine was raised at Dillenburg. In 1560, she married Günther XLI, Count of Schwarzburg-Arnstadt and she moved with her husband to Arnstadt. The marriage was childless, but she reportedly had a good relationship with her husband.[1] They were also on good terms with her brother William. In 1574, they traveled to Breda to mediate between him and the Habsburg government. This attempt was not successful.
Catherine and her husband lived with William in Antwerp, where she continued to live after Günther died. She was present in Delft when her brother was assassinated by Balthasar Gérard. She then took Catharina Belgica, a daughter of William and Charlotte of Bourbon, with her to Arnstadt.