git rebase fatal: Needed a single revision

Question

You need to provide the name of a branch (or other commit identifier), not the name of a remote to git rebase.

E.g.:

git rebase origin/master

not:

git rebase origin

Note, although origin should resolve to the the ref origin/HEAD when used as an argument where a commit reference is required, it seems that not every repository gains such a reference so it may not (and in your case doesn't) work. It pays to be explicit.

Check that you spelled the branch name correctly. I was rebasing a story branch (i.e. branch_name) and forgot the story part. (i.e. story/branch_name) and then git spit this error at me which didn't make much sense in this context.

I ran into this and realized I didn't fetch the upstream before trying to rebase. All I needed was to git fetch upstream

The issue is that you branched off a branch off of.... where you are trying to rebase to. You can't rebase to a branch that does not contain the commit your current branch was originally created on.

I got this when I first rebased a local branch X to a pushed one Y, then tried to rebase a branch (first created on X) to the pushed one Y.

Solved for me by rebasing to X.

I have no problem rebasing to remote branches (potentially not even checked out), provided my current branch stems from an ancestor of that branch.