AFAIK, it tracks its own history separately from other shells. It's not going to read .bash_history (or whatever) to discover your usage patterns - you'll have to use fish for awhile and build some history.

In fact, fish 2.0 will import from .bash_history if it has no history of its own. https://github.com/fish-shell/fish-shell/issues/66

2.0 is not in distributions yet, you probably got the version from 2009. Find your distribution here: http://fishshell.com/files/2.0.0/linux/

And as others have also said, fish knows nothing of your bash history. It'll work fine with quake; use chsh to change shell for your user.

I'm not sure if this is the problem but maybe running fish_update_completions is worth a try.

Of course it autofills your most-used commands. It does it for me, anyway.

It also works for some commands even if you never run them before. For instance curl --i<nsecure> (and I never ran curl --insecure). Also pressing tab will display all curl flags starting with i and a one line description from the man page. Pretty neat.