In 1980, Aoun returned to Lebanon and was appointed later as the interim commander of the mainly Christian 8th Infantry Brigade, that is credited for protecting the Palestinian refugee camp of Borj Al Barajneh from the sinister fate of Sabra and Chatila, and fought against the pro-Syrian Druze and Palestinian militias at the Battle of Souk El Gharb during the Mountain War. During the Israeli invasion, Aoun's office was at the Museum Crossing.