Locale Einstellung auf Debiansysteme
Edit the file /etc/locale.gen and add your locale settings (one set per line), e.g.:
de_DE ISO-8859-1
de_DE@euro ISO-8859-15
As root, run the command „locale-gen“
Add the default language to the file /etc/profile (one of the entries you generated in /etc/locale.gen):
export LANG=de_DE
export LC_ALL=de_DE
export LC_CTYPE=de_DE
To use the new settings with all programs, not only the ones already running, reboot. That’s it.