⚡ TL;DR

git rebase -i HEAD~N

or

git rebase -i <starting-commit-hash>^

git commit --amend --author="Name <email>"

git rebase --continue

git push --force

⚠️ Warning: Modifying commits that have already been pushed to a remote repository can cause history conflicts with collaborators. Use this only when working alone!

📝 Problem: Incorrect Git Author Information

When working on the same GitHub repository across different computers (like work and personal), you might find that your commit author information gets mixed up.
In my case, I had set my company account’s name and email in the global configuration for convenience, and that’s where the trouble began.

As a result, my commits were being recorded with my company email, making it appear as if multiple people were contributing to the project.

I had to go through each commit to correct the author information and then update the history on GitHub. Here’s how I did it:

🧩 Situation Summary

  • Personal and company account information got mixed up in commits
  • Wrong names appeared in GitHub Contributors
  • Decided to clean up the commit history

🛠️ Solution Process

1. Select Commits with Interactive Rebase

git rebase -i HEAD~N

Or if you want to start rebasing from a specific commit:

git rebase -i abc1234^

The ^ symbol means “start rebasing from the commit before this one.”

Or if you want to rebase from the very first commit:

git rebase -i --root

When the list appears, change pick to edit and save.

💡 Quick Edit Tip

With cursor on pick: dw to delete pick → i e to type just the ’e’ of edit (just ’e’ works too) In other words: move cursor, dw, i, e, then save (:wq) and you’re done!

2. Modify Author Information

git commit --amend --author="New Name <newemail@example.com>"

This command overwrites the author information for that specific commit with your specified name and email.
The author you set here only applies to this specific commit, so you don’t need to modify your global or local settings.

3. Continue the Rebase

git rebase --continue

After modifying one commit, use this command to move to the next one.
Repeat this process for all commits you want to fix.

4. Update GitHub

git push origin +main

Finally, you need to force push to update the remote repository with the new history.
+main is equivalent to --force and will overwrite the existing history.

🧭 Conclusion

After this experience, I removed all global settings.
Instead, I now manage name and email settings locally in .git/config for each project.
It’s a bit more work, but it’s a preventive measure to avoid repeating this mistake.

🗂️ TMI
By the way… if you’ve already pushed commits to GitHub and they’ve registered you as a Contributor, fixing the commits won’t change the Contributor list.
I ended up deleting the repository and creating a new one… 😇
(This is really a last resort.)

This experience taught me how a small mistake can mess up your history.
I hope this guide helps if you find yourself in a similar situation.

📚 References
This post was written with reference to madplay’s blog.