The Third Empire of Man
In the 22th century mankind had reached the nearest stars. Unfortunately, it was done by national governments which led to squabbles and fighting amongst the different governments, ending the first Galactic Empire. In the early 23rd century mankind once again reached for the stars. This time it was done by world corporations. This led to an empire defined by greed and slavery, leading to revolt and the end of the second Galactic empire. Then, in the late 24th century, mankind rose again and spread across the universe, this time, more a combination of the two previous empires. Instead of national governments there are planetary governments with a Central government that is ruled by an Emperor and his Senate. Man has discovered other aliens but so far none that have achieved space flight or the technology that man has although he has discovered alien artifacts that are much more advanced than man. The paranoia of discovering a more advanced race has pushed the empire to develop vast military fleets to patrol their empire, especially the central worlds. Most of the outer worlds have been left to fend for themselves, causing them to be rampant with robbery, murders, smuggling, and slavery. Having very little money for a peacekeeper force, they've created licensed bounty hunters whose main job is to try to keep the peace along the outer rim of their empire.