Can't set "LANG" environment variable through /etc/default/locale

Question

I'm running the following setup

• Operating System: Debian GNU/Linux 10
• KDE Plasma Version: 5.14.5

(I'm also using Awesome WM if that's relevant)

Following the Debian wiki, I've run dpkg-reconfigure locales to generate locales and set my /etc/default/locale to the following:

LANG="en_US.UTF-8"
LANGUAGE="en_US:fr"
LC_CTYPE="fr_FR.UTF-8"
LC_NUMERIC="en_US.UTF-8"
LC_TIME="fr_FR.UTF-8"
LC_COLLATE="fr_FR.UTF-8"
LC_MONETARY="fr_FR.UTF-8"
LC_MESSAGES="en_US.UTF-8"
LC_PAPER="fr_FR.UTF-8"
LC_NAME="fr_FR.UTF-8"
LC_ADDRESS="fr_FR.UTF-8"
LC_TELEPHONE="fr_FR.UTF-8"
LC_MEASUREMENT="fr_FR.UTF-8"
LC_IDENTIFICATION="fr_FR.UTF-8"

That is, I'm trying to get every information in english, except for dates, measurements, etc.

When I type locale, I get this:

LANG=fr_FR.UTF-8
LANGUAGE=en_US:fr
LC_CTYPE=fr_FR.UTF-8
LC_NUMERIC=en_US.UTF-8
LC_TIME=fr_FR.UTF-8
LC_COLLATE=fr_FR.UTF-8
LC_MONETARY=fr_FR.UTF-8
LC_MESSAGES=en_US.UTF-8
LC_PAPER=fr_FR.UTF-8
LC_NAME=fr_FR.UTF-8
LC_ADDRESS=fr_FR.UTF-8
LC_TELEPHONE=fr_FR.UTF-8
LC_MEASUREMENT=fr_FR.UTF-8
LC_IDENTIFICATION=fr_FR.UTF-8
LC_ALL=

When I type locale -a, I get:

C
C.UTF-8
en_US.utf8
fr_FR.utf8
POSIX

As you can see, LANG is set to fr_FR.UTF-8, while I'd like it to be en_US.UTF-8. Is there something wrong with my /etc/default/locale syntax ? What could possibly override its content and be considered at login time instead ? KDE regional settings seem to be only american english (and KDE menus/windows are indeed in english).

Answer 1

Well, after @GAD3R's comment, I realized my LANGUAGE variable setting wasn't really consistent with what I wanted : english messages by default, french units / dates, etc. I set it back to only en_US, and something weird happened : when logging into awesome WM, the output of locale was what I'd expected and everything worked fine, but not when logging into KDE Plasma.

With Plasma, I still had LANGUAGE=en_US:fr printed in the locale output ! I finally checked the plasma regional settings, and spotted that there was no default language set. I set it to 'American English', checked the 'Detailed settings' checkbox in the 'Formats' menu (everything was already filled in accordance to the configuration file), logged out and back in and the problem was solved.

I guess that filling stuff inside Plasma settings was necessary, even if everything had been configured through the /etc/ config file already.

Answer 2

You can place this in your .bashrc file as follows

export LANG="en_US.UTF-8"

And put remaining values as so