Kidou Shin Seiki Gundam X

A space colony's declaration of independence from the Earth Federation triggered the 7th Space War, a conflict in which both sides used mobile suits known as Gundams. The Space Revolutionary Army deployed a devastating strategy by dropping numerous colonies onto Earth, causing a seven-year nuclear winter and the collapse of the Federation. Though the Earth was left in ruins, the Space Revolutionary Army failed to follow up with an invasion. Fifteen years later, a new Earth Federation has emerged to reestablish order, while the former colonies continue rebuilding their military. A fifteen-year-old named Garrod Ran stumbles upon a retired Federation mobile suit, the Gundam X, and joins the Vulture ship Freeden in its efforts to prevent history's violent cycle from repeating.