Earth Defense Force
The Earth Defense Force (EDF) is one of the few elements from the first Red Faction that has remained with the series into Red Faction: Guerrilla.
Red Faction
In Red Faction, Parker calls in the EDF to take control of Mars away from Masako's mercenaries and Ultor's guards. The game ends with the colorful message "This facility is now under the command of the Earth Defence Force. Drop your weapons immediately. All armed personnel will be shot on sight."
Red Faction II
The plot of Red Faction II occurs because the EDF brought Capek's nanotechnological work from Mars back to earth.
Red Faction: Guerrilla
50 years after the events of Red Faction, the EDF has become the occupying military on Mars. The main goal of the EDF is now to work and exploit the people as much as possible and send ore back to earth.
After RF:G
It is unknown what is to become of the EDF after the events of Red Faction: Guerrilla.