After the fall of Paris, Marshal Henri Petain, a military hero during World War I, was appointed to boost morale as France was falling under the force of the Nazi invasion. Instead, Petain immediately arranged an armistice with the Nazis.
The armistice, signed by France in June 1940, ceded more than half of France to occupation under Germany. In July 1940, Petain took office as “chief of state” at Vichy, a city in unoccupied France. The Vichy government under Petain collaborated with the Nazis throughout the remainder of the occupation.
https://www.criticalpast.com/video/65675021844_Fall-of-Paris_Arc-de-Triomphe_Champs-Elysees_German-Generals_Les-Invalides