Thomas is the third born son of Duke Robert and Bonnie Calewayn of the Kingdom of Taemar. His family controlled a small duchy in the northern hills of Taemar. He was consecrated to the Silver when he was three months old. The Cult of the Argent is the religion of the Duchy of Cumberland. The people their believe Silver is the dried blood of a dead God that was betrayed by his other creations. The killed him, and his blood poured into the earth and solidified. His goodness and holiness was imbued into the blood, and that is why it is so harmful to evil creatures. His life was always that of hardship and struggle. His father treated him the harshest, breeding him to be a warrior for the family from the beginning of his early life. On his sixteenth birthday, his father granted him the honor of representing the family during the annual tournament hosted in the capital of the family's duchy known as Cumberland. Thomas succeeded and worked his way through the competition, finally reaching the final match. Thomas began to win the fight, but was eventually beaten due to his opponent cheating. Once the match was over his father had him flogged in the families dungeon, and had Thomas's beloved cat skinned alive in front of him, in a twisted way trying to teach Thomas the cost of losing.

At the age of eighteen Thomas is knighted a Knight of the Crown.

At the ripe age of twenty, Thomas Calewayn was married with the blessing of the Argent, to Lucy Crowly, the second daughter to a Duke of Taemar. Not long after the wedding, Lucy found herself pregnant with their first child. Tragedy struck Thomas's life yet again, when he is awakened in the middle of the night to his wife screaming. Several doctors and Argent Ministers are called to the room, but the baby is miscarried. This sends Thomas into a deep depression, turning to alcohol and tobacco to try and fill the dark void that has slowly been eating away at him. His shutting out of everyone and living in a state of perpetual grief eventually leads his wife Lucy to leave him.

Bad luck continues to befall the Calewayn family, when a plague of undeath befalls the Duchy of Cumberland. Duke Robert seals any pass into his mountain duchy, and fights long and hard to quarantine and destroy the undead haunting his woods. He appoints Thomas to lead a small purging squad through a hamlet east of Cumberland. He returns alone. The bulk of the zombie horde had ambushed them on their way back, and he was the only one that made it. His father, overcome with stress from battling the undead for close to a year cannot take another failure, and trying to protect his son from anymore depression causing events, and sends Thomas away in hopes of discovering a cure for the disease. He gifts his son the blade "Grimclaw," the blade of House Calewayn.

Thomas makes a name for himself becoming a Monster Hunter as he traveled the continent, searching for answers. He rooted out several vampire dens, a werewolf, and some witch covens. He became known as "The Grey Knight," due to not only his grey armor, but also his Silver eyes, a trait exclusive to the Calewayn family. As he was traveling to Myridia his boat was attacked by pirates. The boat sank, and he found himself on the coast of Equadia. Stranded and alone, Thomas must discover a way to get back to civilization. Hope arrives in a strange and unfamiliar form...a rhino. Through intense strategy, and clever distraction, Thomas manages to tame the rhino, and rides his new steed back to civilization.

Thomas, with his new rhino named "Parcel," returned to his home continent, and as he was traveling through Terresol, he notices a priest named Sygnis preaching the religion of Syntherion, but he doesn't have time about that religious bullshit. What he really noticed was the priests Silver censure used to spread incense. He followed him after, eventually running into Lord Vronti Kelwynd, where he pledged his sword for his cause.