The Kheewiri were involved in a star spanning civil war for generations. Resembling the large flightless birds of Earth’s distant past, they fought with such ferocity across their 3 settled systems that one world, caught in the middle, was rendered nearly uninhabitable. The other two Kheewiri inhabited worlds faring not much better.
In the wake of a fragile peace, they were left with with little infrastructure or industry that wasn’t dedicated to warfare, and a large population of experienced fighting troops. In an effort to fund their rebuilding, they began to sell their weapons and troops to the highest bidder. Today, centuries later, they are one of the largest private military corporations in the galaxy, taking contracts not only for themselves, but also subcontracting out to other mercenary units across the galaxy.
The TSC supply troops, weaponry, and even fleets to anyone who can pay their fees. At home, the TSC is the de facto government for the trisystems, responsible for its century spanning rebuilding.