Trying to pull files from my Github repository: "refusing to merge unrelated histories"

I'm learning git, and I'm following the Git community book.

Previously (long time ago) I made a public repository on Github, with some files. Now I set up a local Git repository on my current computer, and committed some files. Then I added a remote pointing to my Github page:

[root@osboxes c]# git remote add learnc https://github.com/michaelklachko/Learning-C

That seemed to be successful:

[root@osboxes c]# git remote show learnc
* remote learnc
  Fetch URL: https://github.com/michaelklachko/Learning-C
  Push  URL: https://github.com/michaelklachko/Learning-C
  HEAD branch: master
  Remote branch:
    master tracked
  Local ref configured for 'git push':
    master pushes to master (local out of date)

Now I want to download the files from my Github repo to my computer. I did this:

[root@osboxes c]# git fetch learnc
[root@osboxes c]# git merge learnc/master
warning: refname 'learnc/master' is ambiguous.
Already up-to-date.

However, I don't see any new files in my local directory. How can I get them?

I also tried to do this:

[root@osboxes c]# git pull learnc master
From https://github.com/michaelklachko/Learning-C
 * branch            master     -> FETCH_HEAD
fatal: refusing to merge unrelated histories

BTW, locally I'm on master branch (there are no other branches):

[root@osboxes c]# git status
On branch master
nothing to commit, working directory clean

Try --allow-unrelated-histories

Like max630 commented, or as explained here Git refusing to merge unrelated histories

git checkout master
git merge origin/master --allow-unrelated-histories

Resolve conflict, then

git add -A .
git commit -m "Upload"
git push

While I'm all for unblocking people's work issues, I don't think "push --force" or "--allow_unrelated_histories" should be taught to new users as general solutions because they can cause real havoc to a repository when one uses them without understand why things aren't working in the first place.

When you have a situation like this where you started with a local repository, and want to make a remote on GitHub to share your work with, there is something to watch out for.

When you create the new online repository, there's an option "Initialize this repository with a README". If you read the fine print, it says "Skip this step if you’re importing an existing repository."

You may have checked that box. Or similarly, you made an add/commit online before you attempted an initial push. What happens is you create a unique commit history in each place and they can't be reconciled without the special allowance mentioned in Nevermore's answer (because git doesn't want you to operate that way). You can follow some of the advice mentioned here, or more simply just don't check that option next time you want to link some local files to a brand new remote; keeping the remote clean for that initial push.

Reference: my first experience with git + hub was to run into this same problem and do a lot of learning to understand what had happened and why.

On your branch - say master, pull and allow unrelated histories

git pull origin master --allow-unrelated-histories

Worked for me.

If there is not substantial history on one end (aka if it is just a single readme commit on the github end), I often find it easier to manually copy the readme to my local repo and do a git push -f to make my version the new root commit.

I find it is slightly less complicated, doesn't require remembering an obscure flag, and keeps the history a bit cleaner.