DEV Community
dev.to › donovanrichardson › adding-a-new-remote-and-merging-unrelated-branches-1mkm
Adding a New Remote and Merging Unrelated Branches - DEV Community
August 24, 2020 - But this doesn't mean that Git cannot perform any merge. In fact, all you need to do to merge unrelated branches is to use the flag --allow-unrelated-histories.
Sentry
sentry.io › sentry answers › git › merge branches with unrelated histories in git
Merge branches with unrelated histories in Git | Sentry
July 15, 2023 - Reclone the remote version of the ... If we are attempting to combine two separate codebases, we must pass the flag --allow-unrelated-histories to git merge:...
Git refusing to merge unrelated histories on rebase - Stack Overflow
Then I checked out a local branch from the other repo and only then merged it and suddenly a normal merge commit appeared. Weird. 2016-12-13T13:49:26.807Z+00:00 ... Excellent, works with git pull as well. Was in that "rare event that merges histories of two projects that started their lives independently". git --work-tree="." pull --allow-unrelated... More on stackoverflow.com
Simple question: how to blend two branches with diff commit histories
You can merge unrelated branches. https://reactgo.com/git-merge-unrelated-histories/ More on reddit.com
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June 7, 2022git - Merging two different repositories with different history - Stack Overflow
The --allow-unrelated-histories flag is new-ish; if git merge rejects it, you simply have an older Git that assumes the flag at all times. 2017-08-30T05:07:43.153Z+00:00 ... Save this answer. ... Show activity on this post. My suggestion is just to get one of the repo as principal (let's said first-repo), create a branch ... More on stackoverflow.com
Merging unrelated histories
Since you changed the original commit with your ament, it makes sense to force push now, as you wanted to change the original commit. git push --force-with-lease More on reddit.com
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November 21, 202008:06
How to merge GIT Branches with Unrelated Histories - Git Tutorial ...
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GIT - Unrelated Histories #VisualGit - YouTube
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fatal: refusing to merge unrelated histories #git #gitissue #gitfix ...
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fatal refusing to merge unrelated histories - YouTube
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#GITHUB 02- [RESOLVIDO] FATAL refusing to merge unrelated histories ...
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How to Fix the Git Error "fatal: refusing to merge unrelated ...
GeeksforGeeks
geeksforgeeks.org › git › how-to-merge-unrelated-histories-in-git
How to Merge Unrelated Histories in Git? - GeeksforGeeks
July 23, 2025 - ... Now, you can merge the unrelated histories by using the --allow-unrelated-histories flag. This flag tells Git to proceed with the merge despite the lack of a common commit ancestor.
Medium
spences10.medium.com › git-allow-unrelated-histories-a39a3814b981
Git ` — allow-unrelated-histories` | by Scott Spence | Medium
September 30, 2020 - git merge origin use-ts-bot --allow-unrelated-histories · This brought up, understandably, a few conflicts with the branch I wanted to merge with the origin.
Jeff Kreeftmeijer
jeffkreeftmeijer.com › git-combine
Combine Git repositories with unrelated histories
August 9, 2021 - To combine the two repositories, first add the second repository as a remote to the first. Then, run git fetch to fetch its branch information: ... Then, with the remote set up, merge the second repository’s history into the first by using the --allow-unrelated-histories flag:
Baeldung
baeldung.com › home › git › how to fix git “refusing to merge unrelated histories”
How to Fix Git “Refusing to Merge Unrelated Histories” | Baeldung on Ops
February 6, 2024 - The –allow-unrelated-histories option will tell the Git that we allow merging branches with no common history base, which then should finish the merge without errors. We should note that for the Git version 2.9 or older, this option is not ...
Wouter J
wouterj.nl › 2025 › 12 › merging-unrelated-repositories
Merging Unrelated Projects using Git ~ Wouter J
December 3, 2025 - ... # add a remote, pointing at the new Git project on my local filesystem $ git remote add local ~/projects/github.com/wouterj/docs-builder-new $ git fetch local $ git merge --allow-unrelated-histories local/main
Git Tower
git-tower.com › learn › git faq › how to fix "fatal: refusing to merge unrelated histories" in git
How to Fix "fatal: refusing to merge unrelated histories" in Git | Learn Version Control with Git
1 day ago - git merge --allow-unrelated-histories <branch-name> This option forces Git to proceed with the merge even if it cannot find a common ancestor between the branches.
GitHub
gist.github.com › kingluddite › 7ec82fdfa3700427efa0e5b97196dea6
unrelated-histories.md · GitHub
If you need to bring changes from one branch into another, you can use tools like git cherry-pick or create a patch. Remember that merging unrelated histories should be done with caution, as it can lead to a messy and confusing Git history.
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You can use --allow-unrelated-histories to force the merge to happen.
The reason behind this is that default behavior has changed since Git 2.9:
"git merge" used to allow merging two branches that have no common base by default, which led to a brand new history of an existing project created and then get pulled by an unsuspecting maintainer, which allowed an unnecessary parallel history merged into the existing project. The command has been taught not to allow this by default, with an escape hatch
--allow-unrelated-historiesoption to be used in a rare event that merges histories of two projects that started their lives independently.
See the Git release changelog for more information.
More information can be found in this answer.
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In my case, the error was just fatal: refusing to merge unrelated histories on every try, especially the first pull request after remotely adding a Git repository.
Using the --allow-unrelated-histories flag worked with a pull request in this way:
git pull origin branchname --allow-unrelated-histories
As per 2.9.0 release notes - git pull has been taught to pass the --allow-unrelated-histories option to underlying git merge
Reddit
reddit.com › r/git › simple question: how to blend two branches with diff commit histories
r/git on Reddit: Simple question: how to blend two branches with diff commit histories
June 7, 2022 -
I have a dev branch I need to merge into my main branch. The dev branch I need to merge from a specific commit from Mar 1. The main branch has different commits up to Mar 20 and must be missing a lot from the dev branch. What is the best way of doing this? Trying to research it but the examples are obviously very generic so I figured I'd ask my specific problem in hopes of guidance.
Top answer 1 of 2
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My suggestion:
It can be done in D1's repo or D2's repo:
For D2's side
git remote add [name-for-D1-repo] [D1-repo-url]
git fetch --all
git merge [name-for-D1-repo]/[D1-working-branch] --allow-unrelated-histories
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My suggestion is just to get one of the repo as principal (let's said first-repo), create a branch there (lets said the-other-repo), then dump/copy (no git command, just a plain copy) the tip of the-other-repo in the working directory of the first-repo being the the-other-repo as HEAD, commit the changes, and the merge the-other-repo branch into the HEAD of the "master" branch of the first-repo.
If want to keep the commits history, you could do a rebase.
GeeksforGeeks
geeksforgeeks.org › git › how-to-fix-git-refusing-to-merge-unrelated-histories
How to Fix Git “Refusing to Merge Unrelated Histories”? - GeeksforGeeks
July 23, 2025 - You can do this by using the --allow-unrelated-histories option with the git merge or git pull command. If you are trying to merge two branches with unrelated histories, follow these steps:
Reddit
reddit.com › r/git › merging unrelated histories
r/git on Reddit: Merging unrelated histories
November 21, 2020 -
I created the following repository on GitHub: https://github.com/james/test.git.
Then I proceeded with:
user@guest:~/.../gits$ git config --global init.defaultBranch main user@guest:~/.../gits$ mkdir test && cd test user@guest:~/.../test$ echo "# test" >> README.md user@guest:~/.../test$ git init user@guest:~/.../test$ git add README.md user@guest:~/.../test$ git commit -m "First commit" user@guest:~/.../test$ git remote add origin https://github.com/james/test.git user@guest:~/.../test$ git push -u origin main
And then:
user@guest:~/.../test$ git commit --amend user@guest:~/.../test$ git log --oneline --graph --all * ca82a6d (HEAD -> main) First commit * 085bb3b (origin/main) First commit user@guest:~/.../test$ git merge origin/main fatal: refusing to merge unrelated histories
What did I do wrong and what is the best solution in this case?
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Since you changed the original commit with your ament, it makes sense to force push now, as you wanted to change the original commit. git push --force-with-lease
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The problem comes from the fact that amending a commit changes the hash, and this is your first commit, so there's no related point on the tree. I'll try to explain Every commit has a hash used as Id and when you change your commit on any way (like a rebase or an amend) it changes too. Every tree has an initial commit which is the start of the history for that repository. Every other commit on every branch will have this initial commit as common ancestor. When trying the merge, git tries to find a way to place your new set of commits somewhere on the tree but, since you just changed the root (first) commit it won't find any common ancestor. That's what "unrelated histories" means. Also, that's why you should never change a commit after it was pushed to a remote, even if it's not the first commit (it's not impossible, but everyone's life will be easier). As commented by others, in your case you can just force the merge and everything should be fine.
HackerNoon
hackernoon.com › how-to-merge-two-github-branches-with-entirely-different-stories-rk1n356n
How to Merge Two Github Branches with Entirely Different Stories | HackerNoon
April 7, 2021 - In our example, the almost empty main branch is the obvious selection as the branch to remove, so we need to replace that old disconnected main branch with a new one that shares the starting point of our development branch.
LinkedIn
linkedin.com › pulse › combining-unrelated-git-repositories-when-projects-collide-royer
Combining unrelated Git repositories: When Projects Collide!
May 7, 2022 - 1 cd path/to/project-b 2 git remote add project-a /path/to/project-a 3 git fetch project-a --tags 4 git merge --allow-unrelated-histories project-a/master # or whichever branch you want to merge 5 git remote remove project-a
GitHub
github.com › orgs › community › discussions › 132189
Merging a second branch with the main branch · community · Discussion #132189
July 14, 2024 - Remove: git branch -D main && git branch -m main && git push -f origin main Use instead: git fetch origin main && git merge origin/main --allow-unrelated-histories && git push origin main
Atlassian
jira.atlassian.com › browse › BCLOUD-15952
Support Git merge for branches with unrelated histories
Workaround is: do the merge locally by running: git pull origin master --allow-unrelated-histories git merge origin origin/master add and commit pit push origin master
GitKraken
feedback.gitkraken.com › suggestions › 231952 › support-merging-branches-with-unrelated-histories
Support merging branches with unrelated histories - GitKraken
November 11, 2021 - This mainly comes up when combining two separate git repositories while maintaining both of their commit histories (e.g., if I originally had source code and assets for a game in separate repos and am now combining them into one). This requires `git merge <branch> --allow-unrelated-histories` on ...
GeeksforGeeks
geeksforgeeks.org › git › how-to-fix-git-refusing-to-merge-unrelated-histories-on-rebase
How to Fix - Git Refusing to Merge Unrelated Histories on Rebase? - GeeksforGeeks
May 27, 2024 - Replace main with the name of the branch you want to rebase onto. git rebase origin/main --allow-unrelated-histories · If you're trying to merge instead of rebase, you can use the same flag with the git merge command.