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 Feodorovna (Sophie Dorothea of Württemberg)
Maria Feodorovna married Paul on 7 October 1776. Their marriage resulted in the birth of ten children: