Charles Emmanuel IV of Sardinia

Charles Emmanuel IV (Carlo Emanuele Ferdinando Maria; 24 May 1751 – 6 October 1819) was King of Sardinia from 1796 to 1802. He abdicated in favour of his brother Victor Emmanuel I. He was the brother-in-law of Louis XVI, Louis XVIII and Charles X of France. 
Biography.
"Carlo Emanuele" was born at the Royal Palace of Turin, the eldest son of Victor Amadeus, "Duke of Savoy" and Maria Antonia of Spain. From his birth till his succession he was styled "Prince of Piedmont". He was named after his grandfather Charles Emmanuel III and baptised "Carlo Emanuele Ferdinando Maria". 
In 1775 Charles Emmanuel married Marie Clotilde of France, the daughter of Louis, Dauphin of France and Marie Josèphe of Saxony, and sister of Louis XVI. Although the union was arranged for political reasons, Charles Emmanuel and his wife became devoted to each other. Their attempts to have children, however, were unsuccessful.
He became king at the death of his father on 14 October 1796. In December 1798, the French occupied Turin and forced Charles Emmanuel to abdicate all his territories on the Italian mainland and to withdraw to the island of Sardinia. The following year he tried unsuccessfully to regain Piedmont. He and his wife lived in Rome and in Naples as guests of the rich Colonna family. 
On 7 March 1802 Charles Emmanuel's wife Marie Clothilde died. He was so moved by her death that he decided to abdicate on 4 June 1802 in favour of his brother Victor Emmanuel. Charles Emmanuel retained the personal title of King. 
He died at the Palazzo Colonna in Rome and was buried in the Church of Sant'Andrea al Quirinale.