This kinda piqued my curiosity

The thing about the bad guys is that they’re all interesting to fight in their own ways. Each of them has their own motivations for wanting you dead, and they all have their own unique methods of pursuing the goal. Fortunately for you, and all of humanity, they’re not infallible. Firefights will be all about assessing the unique mixture of all these elements and applying your own force, before it’s too late.

Did ancient humanity do something to these races to warrant extermination? I don't think they want our resources. We only inhabit one city on a planet, that we know of; Earth's and the solar system's resources are there for the taking. Apart from our attempts to regain what once was ours, what threat do we pose to them? And are these races also trying to kill each other, or are they allied against humanity? How does the Traveller fit into all this?

I enjoy being left with more questions than answers. Learning and finding these answers on my own will be that much more enjoyable.Thanks Deej and Urk!