The Knox Event is used to refer to the zombie outbreak that occurs prior to and throughout the game. The event first takes place around Muldraugh and West Point, Kentucky. The incident is considered to have begun on the 4th of July, 1993, American Day of Independence. Just two days later the military evacuated residences from around the affected area and set up blockades in what is now known as the Knox Evacuation. The affected area is given the name: the Exclusion Zone, with the primary camp being south of Louisville.