Today I had a project that I already had in git and I had an existing remote I had already pushed to. Now I wanted to add github as well so I added the repo on github and initialized the repo with a README.mf and a LICENSE file. After adding the remote to the local repo and attempting to pull from it I got the following error:
fatal: refusing to merge unrelated histories
Apparent the way the merge command work has been changed in git v. 2.9 to make sure you do not mix histories by accident. To actually do this use the –allow-unrelated-histories switch. Solution was to add that to my pull command I all was good.
git pull origin master --allow-unrelated-histories
Now I had the README.mf and LICENSE files from github in my local repo so I could edit I push back up. Easy!