The war between ZAFT and Earth Alliance forces began in earnest after the Bloody Valentine tragedy of C.E. 70. It reached a brutal pinnacle during the Second Battle of Jachin Due. Terrible losses on both sides led to cease-fire agreement immediately afterwards. But the agreement did nothing to change the fact that both Naturals and Coordinators continued to possess massive amounts of firepower.
Caught in the crossfire during the Earth Alliance's invasion of Orb, young Shin Asuka saw his parents and sister killed before his very eyes. Left with nothing but his beloved sister's cell phone as a keepsake, Shin came face to face with the reason for the invasion: the Mobile Suit GUNDAM. After fleeing Orb for PLANT, he became a pilot in the ZAFT force in C.E. 73.