Paul Arnault was born on August 21, 1911, in Cherbourg, Handle. His father was worked at the docks in Cherbourg, managing the loading and unloading of ships in the harbor. After studying at Cherbourg University, he entered the Military Academy Saint-Cyr in 1931. Comissioned as a 2nd lieutenant, he was posted to Tafilalet, and two years later to the Maginot Line, where he was made a full lieutenant. In 1935, he was transferred to the French Foriegn Legion and served with the 1st REI, and then with the 3rd REI in Algiers. He entered the 13th DBLE at the unit's formation in February of 1940.

He served with in Norway, as a section leader in the 7th Company, and was commended for his tactical skills. He remains with the 13th in England, and is promoted to captain of the 7th company. He participates in the 13th campaigns of later 1940 and through 1941. At Bir Hakeim, on June 10 and 11, 1942, he is credited with rescuing troops who were lost in the breakout from their pursuing German and Italian foes. He continues with the unit, as a captain, through El Alamein, Tunisia, and into Italy. He is promoted to mahor, and on October 17, 1944, he is made the provisional commander of the 13th. And leads the unit in distinguished actions in Vosges and Alsace in November and January of 1945. He hands over his provisional command to Saint-Hillier on March 24, 1945, and remains in service with the unit through its departure to Indochina the following year.

In Saigon, he is made the assistance commander of the 13th under lieutenant colonel Sairigne, and is subsequently heavily involved in the units reorganization, which leads to his promotion to full colonel, and assuming the command of the 13th, for a second time, in March of 1948. In 1950, he was given command of the 1st REI in Sidi Bel Abbes. In 1953, he creates the SMOLE (Service du Moral et des Euvres de la Legion etrangere), Service of Morale and Works of he Foreign Legion, intended to assist Legionnaires in times of difficulty. In July of 1958, he is made commander of the military subdivision of Vaucluse. He is made a Brigadier General in 1967 and finishes his military career as an assistant General of the 3rd Division in Freigburg. He passes away on November 9, 1988, in Avignon, and buried at Sorgues, Vaucluse.

Below is a list of the decorations/awards Paul Arnault received in his military career:

・Commandeur de la Legion d'Honneur ・Compagnon de la Liberation - decret du 2 juin 1943 ・Croix de Guerre 1939-45 (6 citations) ・Croix de Guerre des TOE (2 citations) ・Medaille Coloniale avec agrafes "AFL", "Erythree", "Libye", "Bir-Hakeim", "Tunisie 42-43", "Extreme-Orient" ・Medaille des Evades ・Croix du combattant Volontaire 1939-45 ・Medaille des Services Volontaires dans la France Libre ・Medaille Commemorative 39/45 ・Medaille Commemorative de la Campagne d'Italie ・Medaille Commemorative d'Indochine ・Medaille Commemorative des Operations de Securite et du Maintien de l'Ordre en AFN ・Medaille Commemorative du Levant ・Commandeur du Nicham Iftikar