The GNU/Linux terminal doesn't display Swedish characters (sv_SE.UTF-8). I've googled, and found several sources with various solutions.
To summarize the error, no matter what guide I follow, is that I get a variation of this: "locale: Cannot set LC_ALL to default locale: No such file or directory".
I'm using Raspbian (Debian 9)
The one thing that worked was:
sudo locale-gen sudo dpkg-reconfigure locales
However, when rebooting, I'm back at the terminal not being able to display Swedish characters.