William I of Württemberg
On 24 January 1816, in Saint Petersburg, he married his first cousin, Grand Duchess Catherine Pavlovna of Russia (1788–1819), daughter of Emperor Paul I of Russia (1754–1801) and Princess Sophie Dorothea of Württemberg (1759–1828). The couple had two children:
Maria Sophie of Bavaria
On 8 January 1859 in Munich at the Allerheiligen-Hofkirche Maria Sophie was married by proxy and then again married in-person on 3 February 1859 in Bari to the Duke of Calabria, the eldest son of Ferdinand II of the Two Sicilies, King of Naples. Within the year, with the death of the king, her husband ascended to the throne as Francis II of the Two Sicilies, and Maria Sophie became queen of a realm that was shortly to be overwhelmed by the forces of Giuseppe Garibaldi and Piedmontese army.