At a young age, Artemis travelled with his parents, as Varisians often do. Unlike most groups, it was simply the three of them. They dealt with their share of the anti-Varisian prejudice many have, but it never affected young Artemis. Who understands the concept of "prejudice" and "different ethnicities" when you're only four? Unfortunately, things you don't know of can hurt you.
While traveling through an area of high tension between the Sczarni underground, root of the anti-Varisian sentiment, and the other ethnicities of the area, Artemis's parents were lynched and killed amid cries of "theives!" and "cons!", blamed for being part of a Sczarni scheme that had taken place in the area that they, of course, had nothing to do with. After these tragic events, young Artemis was left merely with his mother's family scarf to remember his parents by.
After the death of his parents, Artemis was taken in by a female member of the Sczarni by the name of Zeldana. Having tried to protect his parents from the events she blamed herself for, having had a hand in the Sczarni heist that took place, she decided the least she could do to attone was to take care of the boy left behind. Thus did Artemis find his way into the Sczarni faction.
After these terrible events, Zeldana decided to leave the wretched town that took the lives of Artemis's parents, and depart for a new town- and she ended up settling in Hazuk, Bazareene. The local Sczarni there raised Artemis along with Zeldana, and he recieved the type of upbringing one would expect to recieve from rogues, theives, and assassins- the type that trains one to be a rogue, theif, and assassin.
Despite such an upbringing, Artemis was never a killer or cutthroat. Sure, he had a moral code that didn't take the law into account, but never could he be called "evil." Of course the day came when Artemis was sent on jobs, first of theivery, then of assassination; however, he would refuse to do any jobs in which the victim was innocent of anything. To kill without reason, only for money, was never in Artemis's interest- such people are the ones he would take out, not the type of man he himself would become.
Unfortunately, the inevitable day came when Zeldana left for a job and never came back. Sure, Artemis grieved, but he moved on, and continued his training. Other than the obvious, it also included such things as dancing. After all, it helps you sneak into a ballroom dance when you know how to waltz.
Over time, Artemis grew disillusioned with the Sczarni way of life. More and more of the jobs sent his way were immoral in nature. He began to yearn to travel and adventure. And thus, he announced his plans to the faction. No one stopped him; it isn't, after all, like he wanted to betray them, or they were some closed, secret cult. Thus, he simply began to go to the local tavern, and wait for a group to join to travel the world.