The Ubese soldier and pirate Mashaka Vargo spent his entire life searching for some means to avenge his people. Though he was not alive when the Republic attacked Uba IV, he grew up on tales of their treachery, on word of their hatred of his people for their desire to grow as a race. Though they had threatened no one (or so he was taught), the Republic had turned on them and tried to kill them all - and even erased the evidence to boot.
As soon as he was of age, Vargo started a smuggling and pirate ring called the Vargo Liberators which specialized in seeking out and acquiring powerful artifacts. He took on the title of "Mashaka", declaring himself leader of his clan, and used the title to mimic first names given to humans. He knew no one would want to deal with an Ubese for business purposes. He hired a myriad of people to work for him, purchasing vessels and crews to search for anything that could give him the ability to fight back for his people.
One such vessel was the Purgatory's Escape, under the command of Captain Ragnar Starflight. Starflight was a fine captain, but he became arrogant and decided he could fend for himself. He stole the Escape and fled Vargo's service. The two became mortal enemies, and while Vargo still sought items of power to destroy his enemies, he put Starflight at the top of that list.
Though he rarely came across anything of true power - most of those items were carefully guarded by Jedi or Sith - he did manage to find ancient tales of a powerful race, with powerful weapons. Working legitimately, he tracked down the planet of origin and purchased it - the humble ice world of Kuras IV. It was his hope, his desire, that discovering the source of power for the people of that world would lead him to his revenge on those in power - be they New Republic or Imperial.
Having lost all sight of the nobility of his initial wishes for vengeance, Vargo no longer cared who he had to kill to prove that the Ubese were right all along - even if that meant doing to other races what the Republic had done to his. When the crime lord Breggar Lark stole Vargo's deed and placed himself on the planet, Vargo began devising plans to take it over, whether subtly or by force. When Lark was overthrown by Freyel, Arelim Seron, the members of the Solace Colony and the crew of the Purgatory's Escape, Vargo decided this moment of upheaval was his opportunity to invade.
The war lasted a year, concluding in the Second Battle of Kuras IV. When the Scautus Order intervened, Vargo was captured. After several weeks in the colony prison, Vargo was visited by General Enscu and Kratyn vuv Enerkerraz, who appeared to be the general's pet. Enscu offered Vargo a blaster, which the pirate warlord used on himself before Jex Sirri could stop him.