On the outbreak of the Second World War, Prince Louis wrote to the French prime minister, Édouard Daladier, offering to serve in the French Army. His offer was refused, and so he assumed the nom de guerre of Louis Blanchard and joined the French Foreign Legion, seeing action in North Africa before being demobilised in 1941, following the Second Armistice at Compiègne. He then joined the French Resistance and was arrested by the Germans after attempting to cross the Pyrenees on his way to London to join Free French leader Charles de Gaulle. Following his arrest, he spent time in various prisons, including Fresnes. Following his release, he joined the French Resistance groupOrganisation de Résistance dans l'Armee under the name Louis Monnier. Another member of the Charles Martel Brigade to which he belonged was his cousin Joachim, Prince Murat, who was killed in July 1944. Prince Louis himself narrowly escaped death a month later when, on 28 August, he was badly wounded as part of a seven-man patrol that came under attack; he was the sole survivor. Following his recovery, he joined the Alpine Division and was later decorated for bravery. After the war, he lived in Switzerland and, irregularly, in Paris until 1950, when the law of banishment against the heads of France's former ruling dynasties was repealed. Prince Louis became a successful businessman, with a number of financial interests in Africa. In 1951, the prince sent a memorial wreath bearing the Napoleonic 'N' insignia to the funeral of William, German Crown Prince, son of the deposed Wilhelm II, German Emperor. This was seen as an ironic gesture by royalists at the time, given the fact that it was the German House of Hohenzollern that had defeated and dethroned Louis Napoleon's own imperial house during the Franco-Prussian War in 1870. Following Prince Louis's death in Prangins, Switzerland, he designated his grandson, Prince Jean-Christophe Napoléon, as his successor, bypassing his elder son, Prince Charles Napoléon.
Prince Charles Marie Jérôme Victor ; claims headship of the House of Bonaparte and the title Prince Napoléon.
Princess Cathérine Elisabeth Albérique Marie ; married, firstly, on 4 June 1974, in Prangins, Switzerland, Nicolò San Martino d'Agliè dei marchesi di Fontaneto con San Germano, divorced in 1982 without issue. She married, secondly, on 22 October 1982, in Paris, France, Jean-Claude Dualé and had two daughters:
*Charlotte Dualé
*Marion Dualé
Princess Laure Clémentine Geneviève Bonaparte ; married on 23 December 1982 to Jean-Claude Lecomte and had one son:
*Clément Louis Lecomte
Prince Jérôme Xavier Marie Joseph Victor, married on 2 September 2013 to Licia Innocenti.