Born into a family of farmers in northern France, Pétain, after attending the local village school and a religious secondary school, was admitted to Saint-Cyr, France's principal military academy. As a young second lieutenant in an Alpine regiment, sharing the rough outdoor life of his men, he came to understand the ordinary soldier. The extraordinary popularity he was later to enjoy with the rank and file in World War I is believed to have had its origin there.

His advancement until the outbreak of World War I in 1914—he was 58 when he finally became a general—was slow because as a professor at the War College he had propounded tactical theories opposed to those held by the high command. While the latter favoured the offensive at all costs, Pétain held that a well-organized defensive was sometimes called for and that before any attack the commander must be sure of the superiority of his fire power.

After successively commanding a brigade, a corps, and an army, Pétain in 1916 was charged with stopping the German attack on the fortress city of Verdun. Though the situation was practically hopeless, he masterfully reorganized both the front and the transport systems, made prudent use of the artillery, and was able to inspire in his troops a heroism that became historic. He became a popular hero, and, when serious mutinies erupted in the French army following the ill-considered offensives of General Robert-Georges Nivelle (Nivelle, Robert-Georges), then French commander in chief, Pétain was named his successor.

He reestablished discipline with a minimum of repression by personally explaining his intentions to the soldiers and improving their living conditions. Under him the French armies participated in the victorious offensive of 1918, led by Marshal Ferdinand Foch, generalissimo of the Allied armies. Pétain was made a marshal of France in November 1918 and was subsequently appointed to the highest military offices (vice president of the Supreme War Council and inspector general of the army).

Following the German attack of May 1940 in World War II, Paul Reynaud, who was then head of the government, named Pétain vice premier, and on June 16, at the age of 84, Marshal Pétain was asked to form a new ministry. Seeing the French army defeated, the “hero of Verdun” asked for an armistice. After it was concluded, the Chamber of Deputies and the Senate, meeting in Vichy (Vichy France), conferred upon him almost absolute powers as “chief of state.”

With the German army occupying two-thirds of the country, Pétain believed he could repair the ruin caused by the invasion and obtain the release of the numerous prisoners of war only by cooperating with the Germans. In the southern part of France, left free by the armistice agreement, he set up a paternalistic regime the motto of which was “Work, Family, and Fatherland.” Reactionary by temperament and education, he allowed his government to promulgate a law dissolving the Masonic lodges and excluding Jews from certain professions.

He was, however, opposed to the policy of close Franco-German collaboration advocated by his vice premier Pierre Laval (Laval, Pierre), whom he dismissed in December 1940, replacing him with Admiral François Darlan (Darlan, François). Pétain then attempted to practice a foreign policy of neutrality and delay. He secretly sent an emissary to London, met with the Spanish dictator Francisco Franco (Franco, Francisco), whom he urged to refuse free passage of Adolf Hitler's army to North Africa, and maintained a cordial relationship with Admiral William Leahy (Leahy, William Daniel), the U.S. ambassador to Vichy until 1942.

When, in April 1942, the Germans forced Pétain to take Laval back as premier, he himself withdrew into a purely nominal role. Yet he balked at resigning, convinced that, if he did, Hitler would place all of France directly under German rule. After Allied landings in November 1942 in North Africa, Pétain secretly ordered Admiral Darlan, then in Algeria, to merge the French forces in Africa with those of the Allies. But, at the same time, he published official messages protesting the landing. His double-dealing was to prove his undoing.

In August 1944, after the liberation of Paris by General Charles de Gaulle (Gaulle, Charles de), Pétain dispatched an emissary to arrange for a peaceful transfer of power. De Gaulle refused to receive the envoy. At the end of August the Germans transferred Pétain from Vichy to Germany. Brought to trial in France for his behaviour after 1940, he was condemned to death in August 1945. His sentence was immediately commuted to solitary confinement for life. He was imprisoned in a fortress on the Île d'Yeu off the Atlantic coast, where he died at the age of 95.