file2repo.md

Push an individual file from a repo to a new repo and keep command history associated with that file:

git clone <original repo url> temp-repo
cd temp-repo
git remote rm origin
git rm -rf .
git checkout HEAD -- <filename>
git commit -m "<commit message>"
git remote add origin <new repo url> # comments
git pull 
git push -f

Optional: Add new repo as submodule of original repo

git submodule add <new repo url>

WARNING: this way you pull in the entire history of your "original repo" into the "new repo". Not just the history of that one file. This creates at least 2 problems:

• You expose entire project to another project -- e.g. problem if you wanted to publish 1 file of a private project to open source.
• The "new repo" size is increased by the total size of "original repo", not just the added file. Especially painful if you try to split huge repo into smaller ones.

@t7ko, agreed! Do you have any suggestions for alternative methods?

Keep the method but rewrite the history.

git checkout --orphan <new_branch> <your_last_SHA>
git branch -d master # delete the original master
git branch -m master # rename current branch to master
git push -f origin master

If you want/need to keep longer history, you can --orphan an earlier SHA and cherry-pick subsequent commits from the origin master (before you delete it, of course).