[arch-general] Where's my locale gone?

I'm stumped: I've had LANG=en_GB.UTF8 in /etc/locale.conf ever since the switch to systemd, but in the last few days since my previous reboot, something's changed (maybe systemd 216?) and now I find that, even though /etc/locale.conf still contains en_GB, I get: # echo $LANG en_US.UTF8 This is almost certainly related to why I'm getting messed up character encoding in Konsole. In particular, tmux fails to render dividing lines properly, showing accented 'a' characters instead, and similar things happen in Vim. Is there some additional configuration I need beyond /etc/locale.conf now? I've checked locale.gen and rerun locale-gen without any effect. I've also tried rerunning mkinitpio for good measure. Any ideas? Paul