By 1940, he had been given command of the 2nd Armored Cuirassier Regiment. His regiment attempted to block the German blitzkrieg in Belgium, but, like so many other French units, was forced to retreat. When France fell to the Nazis, Touzet du Vigier, now serving the Marshal Petain's Vichy regime, was chosen to head the cavalry department of the army headquarters in Versailles. However, Touzet du Vigier secretly collaborated with the French resistance. His superiors, who ignored his underground activities, sent him to Mascara, Tunisia, where he took command of a sub-division. When the Allies invaded Africa, Touzet du Vigier switched sides to that of De Gaulle's Free French.