Developed by Dynamix, Starsiege is the last in the Earthsiege series; previously named, "Earthsiege 3: Starsiege". It was heavily hyped by Sierra in their in-house magazine, hailing it as one of the greatest 3D games they would ever release. Here is its story:
After Prometheus brought about The Fire in 2602, the populations on Earth, Mars, Venus, and the Moon had been destroyed almost completely. Only a few rag-tag militia remained to fight Prometheus and try to keep the Human race alive. On Earth, the colonies were completely forgotten as Solomon Petresun and Ambrose Gierling formed a trained guerilla force which they dubbed the Terran Defence Force.
The TDF brought together their resources and collective skills and crushed the Cybrid forces a little at a time. Within a few years, the TDF had pushed Cybrid forces back and reduced them to a handful of fledgling groups that TDF scientists could analyze.
Within six months, they had reestablished a handful of military satellites as part of their recovery operations. They were shocked at what they had found: the Cybrids were coming back, with a vengeance.
After fighting back Prometheus a third time, and destroying his nexus on the moon, Earth finally believed it could rest from these battles and began to rebuild. Contact was reestablished with the colonies and terraforming resumed on all of the core planets and some distant moons.
Unknown to the people of Earth, Solomon Petresun and a handful of others in political power were made "immortals," made so by a process developed and originaly implemented by the rogue Cybrid Prometheus.
Now centuries old, Solomon Petresun gained political power as emperor of Earth's Imperial government. He knew that Prometheus would assault Earth again, so he issued the "Fortress Earth Proclamation," which ordered the colonies to provide Earth with their full resources in an effort to build defenses on Terra. The labor he forced on them was excessively opressive, and left the colonies with no real defenses should the Cybrids resurface.
When the colonies rebelled, Petresun sent his immortal son Harabec Weathers to Mars quell the rebellion. Instead, as he expected, Harabec himself rebelled and took command of the rebellion forces.
Within a matter of months, the Martian Rebels began to display astounding skill and tactics combined with unidentifiable alien weapons and technology. Thus, Petresun dispatched his Imperial Knights to crush the Rebels once and for all. However, when the Knights finally arrived, Prometheus, hidden by the silence of space, launched his own assault against the Human forces on the inner planets and began what came to be known as the StarSiege.