The 1st Foreign Regiment (1er RE) is the oldest regiment of the French Foreign Legion in the French Army. Known as the “Camerone regiment,” it has been stationed at the “Camp de la Demande,” renamed “Quartier Vienot,” in Aubagne since 1962, the year the Legion relocated to mainland France after being based in Sidi Bel Abbès. Created in 1841, it is the senior regiment of the Legion. Beyond this historical status, the 1er RE marks a pivotal stage in every legionnaire’s journey: careers begin here at the Selection and Incorporation Center (CSI), and departing personnel complete their out‑processing here as well.

The 4th Foreign Regiment, created in 1920, is the crucible and the school of the Foreign Legion. Established in Castelnaudary for 44 years now, it serves as the CFIM, ENSOA, and specialist schools for every legionnaire—either to be trained or instructed there, or to take part in training the younger ones and thus pass on the torch.

Present in Mayotte in various forms and under different names since 1967, the 5th Foreign Regiment (5RE) established itself under its current name on the Rocher at Dzaoudzi on 1 April 1976. Comprising a permanent command and logistics company and an infantry company on short-duration deployment, it today has nearly 300 personnel.

The 2nd Foreign Infantry Regiment (2e REI) is one of the two infantry regiments of the French Foreign Legion within the 6th Light Armored Brigade. Second among the Foreign Regiments, it was created in 1841. Stationed in Nîmes since 1983, it brings together more than 1,300 service members, including operational reservists, and around thirty civilians.

Created on 1 July 1999, the 2nd Foreign Engineer Regiment (2e REG) established itself at Saint-Christol d’Albion, in the Vaucluse department, on the grounds of Air Base 200. It inherits the historical heritage and traditions of the eighteen Foreign Legion engineer formations that served in Indochina. From its inception, it has taken part in multiple operations, sometimes over long periods, such as KFOR in Kosovo, to which the regiment contributed from 1999 to 2008. In 2000–2001, it was deployed in Bosnia as part of SFOR, then in Côte d’Ivoire from 2005 to 2007 and again in 2011 (Operation LICORNE).