Genesis Prime

The arduous 200 light year space journey from a destroyed Earth is finally over. Now Captain Nick Johns and the crew of the spaceship Genesis must carve out space on a new world to colonize. Unfortunately, their new home planet, Genesis Prime, is already inhabited by three sentient races, one of which is human transplanted from Earth in the 3rd Century BC by aliens needing slave labor. Captain Johns and his crew liberate the enslaved humans and capture the aliens ruling over them.
The human slaves still lived in the 3rd Century culture and viewed the humans of the Genesis as Olympian gods, actually believing Captain Johns was the Olympian god, Zeus. During the liberation they also captured the alien technology, which was far more advanced than that of the Genesis. Eventually they befriend the few remaining aliens and learn the secrets of their technology, one of which is a Plasma Bubble that can transport matter through time and space.
They use this technology to free the last remaining almost extinct aliens from their home world. In doing so, the Genesis attracts the attention of the alien's adversaries that were waging genocide against them. These adversaries now turn their war upon the Genesis colony. Battles rage against these vicious, attacking aliens until the Genesis must face the most ruthless and dangerous race yet, the Human Race.
Captain johns learns with absolute certainty that humans can not be trusted to govern themselves. Humans by their very nature are self-destructive, and given enough time they will destroy themselves. The hardest battles came from within the Human Race and its inherent treachery.