The Rebel Army (also known as the Rebellion Army), led by General Donald Morden, is the main enemy of the Regular Army. They started the war against the Regular Army in 2026. The Rebellion Army was born out of and as a consequence of multiple terrorist groups that began to emerge in the opening of the 21st century. For the majority of that century's first 20 years, the Rebellion Army as we know it did not exist - the terrorist groups had no real cohesion, and though they were a nuisance to the Regular Army they weren't really considered a globe-shaking threat.