Influenced by royalism and Maurrassisme by his stepfather,[3] Cordier joined Action Française at the age of 17 and founded the Cercle Charles-Maurras in Bordeaux.

Cordier admired Charles Maurras and was anti-Semitic, anti-socialist, anti-communist, anti-democratic, and ultranationalist during this period.

In June 1940, while with his family in Bescat, Cordier listened on the radio as Philippe Pétain announced the French surrender to Germany and the armistice.

In Lyon, he managed to recruit Laure Diebold, Hugues Limonti, Suzanne Olivier, Joseph Van Dievort, Georges Archimbaud, Laurent Girard, Louis Rapp, and Hélène Vernay.

To create this council, many compromises had to be made between Moulin and Pierre Brossolette, a colleague of Charles de Gaulle.

[10] As he would later tell in his autobiography, Alias Caracella, Cordier abandoned his royalist beliefs, partly because he felt betrayed by his idol, Charles Maurras, who supported Vichy France.

He dedicated himself to political activism, having given up his far-right beliefs after becoming acquainted with the radical socialist Jean Moulin.

In November 1956, he began exhibiting his artworks, which would show the start of a long and successful career in art dealing.

He was a friend of Roland Barthes,[17] as well as a tutor for Hervé Vilard and inspired him to pursue a singing career.

[18] In 2020, during the commemoration of the Appeal of 18 June, Prime Minister of the United Kingdom Boris Johnson honoured the last four Companions of the Liberation: Cordier, together with Edgard Tupët-Thomé, Pierre Simonet, and Hubert Germain.

The four men were named to the Order of the British Empire by Ambassador of the United Kingdom to France Ed Llewellyn.

Their commitment ... allowed that on the day of the landing the allies saw a France rising from the shadow in which it was lurking, ready to take back its destiny in hand".

[23]Minister of the Armed Forces Florence Parly and her Secretary of State, Geneviève Darrieussecq issued a joint statement, saying "a romantic life which is dying out, spent in the service of Liberty, for the greatness of France".