On 1 July 1981 the Chief of Staff of the French Army enacted the creation of an inter-arm brigade placed under the orders and command of the Foreign Legion Groupment (G.L.E), headed by générals[2] Paul Lardry and Jean-Claude Coullon.

Général de brigade Jean-Claude Coullon was also in charge of the 2nd Foreign Parachute Regiment (2e REP) in 1982, through the putting-in-place of Operation Épaulard I spearheaded by lieutenant-colonel Bernard Janvier.

The insignia of the 31st Brigade is a silver rectangle, bordered to the left by green and red stripes, representing the Legion and bordered to the right by red and blue stripes, representing the Troupes de marine.

At the bottom left features Poseidon armed with a trident, forming out of a silver wave, recalling the intervention capacity capability of the brigade in any lieu, by maritime including aeronaval, aerial, or other maritime means of displacement.

The insignia was realized in July 1981, following a contest at the corps units forming the brigade.