Oliveira and the Marauders worked with House Arano prior to the coup that led to the Aurigan Directorate,  Kamea Arano called upon them for the Restoration War, during which his unit fought in several notable battles. At times they were known to field SLDF-era Assault 'Mechs.
Darius grew up on Nassau Heights, one of the hab stations orbiting the Aurigan Coalition world Artru. Thirty decks of economic stratification, with the corporate suits on the upper decks and everyone else crammed into the lower ones. His father was a deckhand and the whole family lived on Deck 28, two levels up from the bottom, with other station maintenance personnel. Twelve hours a day, six days a week, his father would load and unload cargo shuttles. Vacuum-sealed quillar and nutrient paste for common people, and luxury goods for the suits upstairs. According to Darius, he must've unloaded a thousand cases of Cassildan eel roe-plump, succulent eggs the size of melon balls. Never got to taste any, though. Any one of those tins would've cost him a half a year's wages.
Suffice it to say that Darius got an eyeful of what he did not want to be on Nassau Heights, and did what he had to do to change his circumstances. By the age of sixteen, he struck out on his own, leaving with a handful of skills, an enormous web of contacts, and a rucksack full of that expensive caviar. And once he made it off of Nassau Heights, he never, ever looked back. He took up a career as a MechWarrior and eventually made it to the position of Executive Officer of Markham's Marauders.
High Lord Tamati gave the company the job back in 3019. They were supposed to be assisting the Royal Guard to round up and eliminate a pirate clan on Fjaldr. Commander Markham thought it would be easy money, but it turned out to be anything but. They lost a dozen MechWarriors in the three months of the Fjaldr campaign and most had to be hosed out of their cockpits. Would've been more if it wasn't for Sir Raju Montgomery. The Mastiff saved the Marauders' asses on more than one occasion and went out of his way to do it. And the thing is, he didn't have to. A lot of people in Mastiff's position would've used the mercs as cannon fodder, but that wasn't his way. He treated the Marauders as if they were his own.
Birth year is a guess based on age in character profile given in Kickstarter update and assuming timeline of 3025.
- Harebrained Schemes LLC: Kickstarter Update #33: "Introducing the Main Characters"
- House Arano (The Aurigan Coalition) p. 12
- House Arano (The Aurigan Coalition) p. 38
- House Arano (The Aurigan Coalition) p. 37
- House Arano (The Aurigan Coalition) p. 39
- House Arano (The Aurigan Coalition) p. 41
- House Arano (The Aurigan Coalition) p. 42
- House Arano (The Aurigan Coalition) p. 44
- House Arano (The Aurigan Coalition) p. 49
- House Arano (The Aurigan Coalition) p. 25
- House Arano (The Aurigan Coalition) p. 55