Background
He became head of the formerly reigning royal House of Württemberg on the death of his father in 1939. His first marriage was to Archduchess Helena of Austria, Princess of Tuscany (born 30 October 1903 in Linz. Died 8 September 1924 in Tübingen), daughter of Archduke Peter Ferdinand of Austria (younger son of Ferdinand IV, Grand Duke of Tuscany) and Princess Maria Cristina of Bourbon-Two Sicilies (daughter of Prince Alfonso, Count of Caserta), on 24 October 1923 in Altshausen.