refusing to merge unrelated histories

Fixing Git: refusing to merge unrelated histories

I have a new project and I add git repo later on after the project finished.
After setup remote repo to my project, I got this kind of error when pulling data from the repository.

fatal: refusing to merge unrelated histories

The problem fixed by adding this argument to git command “–allow-unrelated-histories”.

$ git pull upstream master --allow-unrelated-histories

Reference: https://stackoverflow.com/a/37938036/1936697