He married Sophie Albertine (15 December 1728 - 10 May 1807), a daughter of August Gottfried Dietrich, Count of Beichlingen and Sophie Helene, Countess of Stoecken.
He succeeded his brother Karl Eugen as Duke of Württemberg in 1793, and reigned until his own death in 1795, when he was succeeded by his younger brother Frederick Eugen.