I recently switched from bash to zsh. In bash one way (besides recursive search) that I used to find previously-run commands was history | grep whatever, where whatever is the bit of command I remember.

In zsh, this isn't working. history returns only a few items, even though my .zsh_history file contains many entries, which I have configured it to do.

How can I output my whole history, suitable for searching with grep?

(Note: I started out using ryanb's dotfiles, so perhaps it's a problem with his default settings?)