She married on 6 July 1512 in Freiberg Duke Henry the Pious of Saxony.

Catherine sympathized early with Martin Luther's teachings, while her husband suppressed the Reformation until 1536 for fear of his brother, the reigning Duke George the Bearded.

When duke George tried bear down on Catherine, she told the envoy: You could do me a big favor by leaving Freiberg right now.

In 1539, after the death of Duke George, the couple moved to Dresden and brought the Reformation there.

In 1560, she published a book on etiquette for ladies, which is culturally and historically very interesting.