With the defeat of France in 1940 her fledging airborne forces were torn in two. Pre-war France had centred her airborne force within the air force. These units were known as Groupes Infanterie de l'Air. At the time of the Armistice some of these airmen determined to fight on with de Gaulle's Free French, others remained within the forces under Vichy control.
The 2 Groupes Infanterie De l'Air (601 and 602) ended up in North Africa under Vichy control. A number of other troops who evaded to the UK formed the 1er Compagnie d'Infanterie de l'Air (1 CIA) , under Captain Berge. Part of this unit was assigned to the Free French Secret Service (B.C.R.A.) for missions in Occupied France, the remainder was shipped to the Middle East where, after it was renamed the 1er Compagnie de Chasseurs Parachutistes (1er CCP.), it eventually ended up forming the French Squadron of Stirling's Special Air Service.
Back in the UK a second company was formed, 2eme Compagnie d'Infanteria de l'Air (2 CIA). In December 1942 the 1er CCP in the Middle East was retuned to the UK. Some troops were sent to Tunisia to work with the 2nd SAS Regiment as the 2eme Compagnie Parachutiste S.A.S. (2 CPSAS).
Early in 1943 the elements of the 1er C.C.P. and the 2 CPSAS are merged into the 2 CIA and the whole is renamed as the 1er Batallion d'Infanterie de l'Air (1er BIA). In November 1943 units arriving from the Lebanon and Algeria formed the 3eme Batallion d'Infanterie de l'Air (3eme BIA). The 1er BIA is renamed to the 4eme BIA.
In North Africa the GIA 601 and 602 are merged to form the 1er Regiment de Chasseurs Parachutistes. Trained and equipped by the US, the 1er RCP are scheduled for a number of airborne missions but they are all cancelled and the regiment will find itself used as an elite infantry unit.
In January 1944 the 3eme and 4eme BIA are attached to the newly formed SAS Brigade as 3SAS and 4SAS respectively. Both units are used during Overlord. In November there is a change of designation again as the units are renamed as 3eme Regiment de Chasseurs Parachutiste (3 RCP) and 4 RCP.