The Human-Dirge War, or simply the Dirge War, was a global military conflict which involved a every one of the world's nations, and the forces of the alien civilization known as the Dirge. The war involved the mobilization of over 1 billion military personnel, making it the most widespread war in history. In a state of "total war", the participants placed their entire economic, industrial, and scientific capabilities at the service of the war effort, erasing the distinction between civilian and military resources. Over four billion people, the majority of whom were civilians, were killed, making it the deadliest conflict in recorded history.