'A' was the initial commit, but now you want 'B' to be the initial commit. git commits are whole trees, not diffs even if they are normally described and viewed in terms of the diff that they introduce.

This recipe works even if there are multiple commits between A and B, and B and C.

# Go back to the last commit that we want to form the initial commit (detach HEAD) git checkout <sha1_for_B> # reset the branch pointer to the initial commit, # but leaving the index and working tree intact. git reset --soft <sha1_for_A> # amend the initial tree using the tree from 'B' git commit --amend # temporarily tag this new initial commit # (or you could remember the new commit sha1 manually) git tag tmp # go back to the original branch (assume master for this example) git checkout master # Replay all the commits after B onto the new initial commit git rebase --onto tmp <sha1_for_B> # remove the temporary tag git tag -d tmp 

A was the initial commit, but now you want B to be the initial commit. git commits are whole trees, not diffs even if they are normally described and viewed in terms of the diff that they introduce.

This recipe works even if there are multiple commits between A and B, and B and C.

# Go back to the last commit that we want # to form the initial commit (detach HEAD) git checkout <sha1_for_B> # reset the branch pointer to the initial commit, # but leaving the index and working tree intact. git reset --soft <sha1_for_A> # amend the initial tree using the tree from 'B' git commit --amend # temporarily tag this new initial commit # (or you could remember the new commit sha1 manually) git tag tmp # go back to the original branch (assume master for this example) git checkout master # Replay all the commits after B onto the new initial commit git rebase --onto tmp <sha1_for_B> # remove the temporary tag git tag -d tmp 

'A' was the initial commit, but now you want 'B' to be the initial commit. git commits are whole trees, not diffs even if they are normally described and viewed in terms of the diff that they introduce.

This recipe works even if there are multiple commits between A and B, and B and C.

# Go back to the last commit that we want to form the initial commit (detach HEAD) git checkout <sha1_for_B> # reset the branch pointer to the initial commit, # but leaving the index and working tree intact. git reset --soft <sha1_for_A> # amend the initial tree using the tree from 'B' git commit --amend # temporarily tag this new initial commit # (or you could remember the new commit sha1 manually) git tag tmp # go back to the original branch (assume master for this example) git checkout master # Replay all the commits after B onto the new initial commit git rebase --onto tmp B # remove the temporary tag git tag -d tmp 

'A' was the initial commit, but now you want 'B' to be the initial commit. git commits are whole trees, not diffs even if they are normally described and viewed in terms of the diff that they introduce.

This recipe works even if there are multiple commits between A and B, and B and C.

# Go back to the last commit that we want to form the initial commit (detach HEAD) git checkout <sha1_for_B> # reset the branch pointer to the initial commit, # but leaving the index and working tree intact. git reset --soft <sha1_for_A> # amend the initial tree using the tree from 'B' git commit --amend # temporarily tag this new initial commit # (or you could remember the new commit sha1 manually) git tag tmp # go back to the original branch (assume master for this example) git checkout master # Replay all the commits after B onto the new initial commit git rebase --onto tmp <sha1_for_B> # remove the temporary tag git tag -d tmp