H.I.H. Princess Marie Clotilde Eugénie Alberte Laetitia Geneviève Napoléon was born in Brussels on March 20, 1912. She was the only daughter and eldest child of H.I.H. Napoléon Victor Jérôme Frédéric, Prince Napoléon (b.Paris July 18, 1862;d.Brussels May 3, 1926), and of H.R.H. Princess Clementine Albertine Marie Leopoldine of Belgium (b.Laeken July 30, 1872;d.Nice March 8, 1955). Marie Clotilde's birth was followed two years later by that of her only sibling, Louis Jérôme Victor Emmanuel Léopold Marie.
On October 17, 1938, at Our Lady of Victories Church, on Kensington High Street in London, Marie Clotilde married the Russian Count Serge de Witt (b.Moscow December 30, 1891;d.Cendrieux July 21, 1990). Serge was the son of Count Oscar de Witt and Lydia de Fidler. He had gained the rank of Captain while serving in the Russian Imperial Calvary. The couple were married for fifty-one years and had a total of ten children (in order of birth: Marie Eugénie, Hélène, Napoléon Serge, Yolande, Véra Geneviève, Baudoin, Isabelle, Jean Jérôme, Wladimir, and Anne Clémentine). Sadly, Napoléon Serge and Yolande de Witt died in infancy.
Most of Marie Clotilde's daughters married members of the French nobility. One of Marie Clotilde's grandsons from such a marriage, Count Cyril Amédéo de Commarque (second son of Véra Geneviève de Witt and Raymond Godefroy, Marquis de Commarque) married Princess Cécile Marita Dorothea zu Hohenlohe-Langenburg in 1998.
Princess Marie Clotilde died at the Château de la Pommerie in Cendrieux on April 14, 1996 at the age of eighty-four.