Sicarians

The Sicarians (from Old Basic sicarii, meaning "assassins" or "dagger-bearers"), also known as the Rakites, were an pirate organization and pseudo-religion comprising Humans of various homeworlds that attacked Republic worlds and merchant ships.

They had developed such a distinct culture that they developed their own national identity, complete with a language of mysterious origin and even a religion that would later come to be known as Rakism, named after the warlord Rakal mu-Panan. They were strictly humanocentric, and had a deep-seeded hatred for any non-Human. They gradually developed a unique language that spread to hundreds of rimward worlds and developed into other similar languages over the millennia.

History
Their true origin is unknown, though evidence concludes that the Sicarians were operating as early as 9000 BBY and were founded by a space explorer and warlord named Rakal mu-Panan. Rakal dictated that only his sons and their sons may continue to command the Sicarians following his death, leading to the establishment of a nomadic hereditary monarchy that waged war with the Republic whereever an opportunity was seen. Their exact goals became unknown as millennia passed, though one of their tenets remained constant: the Republic is an enemy. Their pseudo-religion, Rakism, dictated that the Sicarians were not to take the territory of those they attacked, but instead simply take their resources, spread the word of Rakism, and move unto the next target; any of the Rakite warships that broke formation from the fleet were no longer considered Sicarian, and would be hunted down and destroyed per Panite "law".

With an ever-growing fleet of warships that served as their homeland, they pillaged Republic colonies and assaulted/captured merchant fleets whenever they were stumbled upon. They had grown to be such a thorn in the Republic's side, in fact, that entire Republic war fleets were assembled over the centuries that were entirely dedicated to investigating pirate attacks and tracing them back to the Sicarians. After more than two millennia of maintaining a massive fleet and waging space battles with the Republic, the Sicarians initiated their next plan: Zhimag dol-Kaffap (meaning "Expedition to the Void"). This great expedition saw the Sicarian fleet, now numbering more than 230 massive warships crewed by over 2 million Humans, traveling as far north into the Outer Rim as per the "prophecy" established by Rakal mu-Panan to finally adopt a settled lifestyle - to establish colonies along their way. This prophecy dictated that "each one warship shall settle upon one world and the crew of that warship shall be its colony should they succeed in defeating the previous wanderers of that land", meaning that for every warship in the fleet, one world would be settled by the Rakites by way of overturning the world's previous inhabitants.