Second World War
After the Battle of France, La Rocque accepted the terms of the June 1940 Armistice "without restrictions". La Rocque also accepted the "principle of collaboration", upheld by Marshal Philippe Pétain in December 1940. However, at the same time, he was attacked by sectors of the far right, which claimed that he had founded his newspaper with funds from a "Jewish consortium". His attitude remained ambiguous, as he wrote an article in Le Petit Journal of 5 October 1940, concerning "The Jewish Question in Metropolitan France and North Africa" (La question juive en métropole et en Afrique du Nord). H. R. Knickerbocker wrote in 1941 that the Petit Journal with La Rocque as editor "assumed a more courageously anti-German attitude after the armistice than did most other papers published under the control of the Vichy government". On 23 January 1941, La Rocque was made a member of the National Council of Vichy France. La Rocque approved the repeal of the Crémieux decrees, which had given French citizenship to Jews in Algeria, but he did not follow the Vichy regime in its racist radicalization. He also condemned the ultracollaborationist Legion of French Volunteers Against Bolshevism.
La Rocque changed orientation in September 1942 by declaring, "Collaboration was incompatible with Occupation". He entered contact with the Alibi Network (Réseau Alibi), which tied to the British Intelligence service. He then formed the Klan Network (Réseau Klan) Resistance network with some members of the PSF. La Rocque rejected the laws on the STO, which forced young Frenchmen to work in Germany, and he also threatened to expel any member of the PSF who joined Joseph Darnand's Milice or the LVF.
He was arrested in Clermont-Ferrand on 9 March 1943 by the SIPO-SD German police, along with 152 high ranking PSF members around France. He was deported first to Jezeří Castle, now in the Czech Republic; then to Itter Castle, Austria, where he found former President of the Council Édouard Daladier and Generals Maurice Gamelin and Maxime Weygand. Ill, he was interned in March 1945 in a hospital in Innsbruck and was freed by U.S. soldiers on 8 May 1945. He returned to France on 9 May and was placed under administrative internment. Though the official justification was to protect him against violence from the left, he suspected that his arrest was a deliberate effort at suppressing his political activities.
Years of imprisonment had left him seriously ill, but he received no medical attention until his detention was deemed unlawful and he was moved to house arrest in November 1945. He died on 28 April 1946 following an operation to treat an ulcer which had developed in his esophagus.