rewrites happen before location {} blocks are considered (if the
rewrite is on a global level) correct?

so

location /foo {
this will never be computed
}

rewrite /foo/bar /somethingelse permanent;

That's at least what it seems to me, unless I'm missing something.

It doesn't seem like ^~ ~* etc seem to matter either. Or is it all
depending on the order in the config file?