She married Prince Christian August of Anhalt-Zerbst and had five children, two of which reached adulthood. Her daughter Sophie went to Russia, took on the Russian name Ekaterina Alexievna, married another German who happened to be incompetent, and became Tsaritsa Catherine II. Johanna accompanied Sophie to Russia, but was thrown out of Russia when Catherine married, apparently because she was spying for Frederick II (the Great) of Prussia.