Git Rebase Onto explained with a script you can run on an empty directory

Git Rebase Onto Script Example

git init
git checkout -b original
git commit --allow-empty -m 'Commit 1'
git commit --allow-empty -m 'Commit 2'
git commit --allow-empty -m 'Commit 3 (third)'
git tag third
git commit --allow-empty -m 'Commit 4'
git commit --allow-empty -m 'Commit 5'
git tag fifth
git commit --allow-empty -m 'Commit 6 (sixth)'
git commit --allow-empty -m 'Commit 7'
git commit --allow-empty -m 'Commit 8'

git checkout -b rebased

git commit --allow-empty -m 'Test Commit 1'
git commit --allow-empty -m 'Test Commit 2'
git commit --allow-empty -m 'Test Commit 3'

git rebase --onto third fifth

git log --format='%C(bold blue)%s' original
git log --format='%C(bold yellow)%s' rebased