How to rewrite history in a git repo

git-rewrite-history.sh

#!/bin/sh

## change commits
#######################################################
git filter-repo --commit-callback '
msg = commit.message.decode(\"utf-8\")
newmsg = msg.replace(\"old string\", \"new string\")
commit.message = newmsg.encode(\"utf-8\")
' --force

## change commiter - filter-repo
#######################################################
cd repo
git filter-repo --mailmap my-mailmap
#my-mailmap file content
Correct Name <correct@email.com> <old@email.com>

## change commiter - filter-branch
#######################################################
git filter-branch --env-filter '
OLD_EMAIL="you@wrong.email"
CORRECT_NAME="Your name"
CORRECT_EMAIL="You@correct.email"

if [ "$GIT_COMMITTER_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_COMMITTER_NAME="$CORRECT_NAME"
    export GIT_COMMITTER_EMAIL="$CORRECT_EMAIL"
fi

if [ "$GIT_AUTHOR_EMAIL" = "$OLD_EMAIL" ]
then
    export GIT_AUTHOR_NAME="$CORRECT_NAME"
    export GIT_AUTHOR_EMAIL="$CORRECT_EMAIL"
fi
' --tag-name-filter cat -- --branches --tags -f

git push --force --tags origin 'refs/heads/*'

From https://help.github.com/articles/changing-author-info/