The French Foreign Legion or Légion Etrangère (L.É.) in French, is a branch of the French Army. It was created so foreign nationals who wanted to serve in the French Army could do so.
Georges Batroc joined the French Foreign Legion after he moved to Algeria. He eventually transferred to the DGSE, and, after his service with their Division Action (Action Division), he became a freelance mercenary. This information was presented to Black Widow, Captain America, and Brock Rumlow's STRIKE team on board a Quinjet en route to rescue the Lemurian Star.