Kashak was born one of a pair of maternal twins. He and his brother Mashak never knew their Variag mother, as she died during childbirth. Their father was a Black Troll, an Olg-hai sworn to the service of "The Eye". It did not matter, as she had conceived, and carried the children under force, and threat of violence. They were raised by their fathers people---the evil creatures of Mordor.
From the beginning they were groomed, and trained for the highest ranks of the Dark Lords armies. They would serve only the eye, directing orcs, common trolls, and even mannish forces against the free peoples. When Kashak's talent for channeling, and Mashak's talent for essence were discovered they were immediately placed among the acolytes of the dark preisthood. Everyone around them believed they would become great warlords and powerful spellcasters. their destiuny as generals of the Dark Lords forces was assured.
But no one asked them what they wanted. The blood of their Variag mother ran strong in their veins, and they rebelled against authority. Mashak loved the study of magic, with no particular bent towards evil. Kashak loved plants, and growing things, and healing the injuries of the black lands poor misbegotten creatures. They grew more, and more disgusted, and disillusioned. Finally they gathered what they could and fled to follow their own destiny.
Mashak took with him his pet "killer" rabbit, which had found when it was a baby. He had hand raised it , eventually developing a mental bond. Kashak took along his most prized possession, his iron staff topped with an iron, fanged skull. It was the only heirloom of his mother's family and people that he ever had. Kashak had spent much time among the Black Numenorean servants of darkness acquiring knowledge of cookery, herbs, and poisons. He also picked up their fascination with the stars, and studied astronomy, navigation, and star-gazing.
Both Kashak and Mashak have an inscription tatooed on the inside of their left forearms:
....and we dance on the skulls of the dead all around, and we watch as the murdered rise through the ground......
It is a fragment of prophecy from their Variag grandmother who died trying to prevent her daughter being taken by trolls. The rest of the poem has been lost with the deaths of their mother and grandmother. It was tatooed on them at birth.
After fleeing Mordor they wandered for a time in southern Gondor. However they found most people, and indeed the authorities to be averse to their presence. They took to travelling by night and hiding during the day, until the arrived in Dor-en-Ernil. there they encountered a few friendly faces, and became part of a party of adventurers. They went on several missions to deal with problematic trolls in the area outside of Dol Amroth, and finally became accepted by the locals at least.
Mashak, and the rest of the group then sank to sitting on their "laurels", and slowly spending their booty on women, and ale. Kashak implored them to continue their adventuring activities, but they would not be budged from the taverns while there was coin in their pockets. Kashaks blood burned to travel, and see foreign lands, and meet new people, so finally he did the unthinkable. Kashak gathered his gear, and funds. He said goodbye to his brother while Mashak was asleep. Then he went down to the docks, and signed on as crew on a ship bound for Cardolan.
For the first time in his life he was totally alone and disconnected. There was no one around who knew him, or had any expectations of him, or any hold on him. The vessel rounded Andrast, making a few stops to trade, and then made for the mouth of the Gwathlo river. Again stopping along the way several times, the small ship slowly made its way upriver to Tharbad. There Kashak took his pay, and his leave, and disembarked. Unfortunately his welcome was not as warm as he would have liked.
The authorities in Tharbad were not thrilled with the disembarkation of a seven foot tall Half-troll witch, no matter what reputation he claimed in Dol Amroth. Kashak was lucky not be killed outright or lynched but soon found himself in jail. Escaping, he fled into the wilderness. There he wandered for a time, avoiding people, and settlements, before finally coming into Rhudaur. Luckily he ran into Larec, and Rena. The Uruk was much more accepting of the Olog than "normal" people were, and Larec, and Kashak became fast freinds. Kashak also likes his other new companions who treat him well despite the fact that they are human, and elven. In fact he thinks the elf, Lalaina, is quite attractive. He has not said anything to Lalaina yet because he has been observing how Rena reacts to Larecs advances, and is convinced that he doesn't have a chance.