Formerly a technical requirement, but one that was widely ignored. Even the Legion's traditional marching song Le boudin identifies the Legion's troopers as les Alsaciens, les Suisse et les Lorrains. And it's a good bet that the accents of a good many of the *Swiss* Legion enlistees owed more to the streets of Maresilles or Paris than to those of Thun, Basel or Bern.
Nowadays [since the mid-1970s] about a third of those in the Legion Etranger are of French nationality.
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