When he was but a baby, Gabriel was left at the gates of the Brotherhood of Light covenant. The Brotherhood gave Gabriel his name and raised him as their own. They trained him to be a warrior, Gabriel over the years developing an unprecedented mastery of the fighting arts. Due to his love of mountains and high places, he took the surname Belmont. It was during these years where he met Marie, who he ultimately married; the kind, gentle Marie proved to be the perfect counterbalance to his "dark moods," bringing to his life a sense of calm.

Though, Gabriel's life began falling to pieces when Marie was killed by an unknown assailant as he carry out a mission for the Brotherhood--or so he believed. In reality, it was Gabriel who murdered Marie while under influence of the Devil Mask, whose controller instigated the event and left Gabriel without memory of it. In the days that followed, his depressive temperament only worsened, his dark moods manifesting as ever-increasing anguish over the loss of his beloved wife. Things would get much worse: One year before his wife had been murdered, Gabriel was sent out on an assignment to deal with the menacing Daemon Lord; the entire undertaking was merely a distraction under the cover of which the Brotherhood visited Marie with news of a dire prophecy that been revealed to them via a mystical amulet that was somehow connected to the prognosticating Mirror of Fate. They learned of a terrible, unavoidable destiny that awaited Gabriel and informed Marie that her only child, Trevor, must be taken from her in order to protect him from his soon-cursed father. Gabriel, who had spent much of his time working for the covenant, never knew of the child's birth.

In an era of hopeless darkness, wherein the forces of evil had used dark magic to separate mankind from Heaven, chaos had enveloped the world. Looking to discover the reason behind the affliction, the Brotherhood requested that Gabriel, its finest knight, embark on a journey to discover the cause; driven by a burning desire to avenge his wife's death, Gabriel accepted the mission. Taking possession of his famed Combat Cross, which was created by the alchemist Rinaldo Gandalfi, he headed out in search of an elder god named Pan, whose trials convinced Gabriel that he had been brought there to receive a message from his dead wife. Too, he was rescued by and befriended Zobek, who was a member of the Brotherhood and an old acquaintance of Pan; the experienced Zobek would come to Gabriel's aid many a time. Later interaction with Marie's visage revealed the possible reasoning behind the realms being split; though the message was not completely clear, she spoke of the "Lords of Shadow," who might, she said, know the answers. Regardless, the path was to Gabriel clear: He must claim the power of the Lords of Shadow, thereby becoming God's vassal and capable of entering the Land of the Dark Lord, whose defeat would bring about the reuniting of the Heaven and Earth

As he scoured the countryside, through villages, castles, forests, and all variety of unholy land, Gabriel confronted and destroyed the Lords of Shadow, inheriting their power and growing ever-more-powerful. He suffered many setbacks--he was responsible for the deaths of newfound friends and endured violent, emotionally charged confrontations with those he had considered allies, including Pan, whose reasoning for his hostile actions was at best cryptic. It wasn't long before the weary Gabriel arrived on the doorstep of Hell, itself, where he was betrayed by even Zobek, who revealed himself to be the final Lord of Shadow; Zobek had been manipulating Gabriel from the start, orchestrating the deaths of his companions, including his wife, and keeping him in a state of despondency as to ensure that he would not become too powerful. The final, crushing blow came about as a result of Zobek's prodding--a flashback in which Gabriel remembered that it was he who murdered his own wife. The distraught, prone Gabriel was thus killed by Zobek, whose celebration didn't last long. Zobek, that is, was summarily destroyed by the Dark Lord, who was manipulating even him to bring about this desired outcome.

It was the interference of Marie's soul that convinced the reaping spirits to let Gabriel live, to finish his mission. With the power of God in hand, Gabriel fought with supernatural flare and defeated the vile Dark Lord, Satan, who was then banished from this world. His victory allowed for the spirits to finally reach Heaven. Gabriel had triumphed, but he no longer had the will to live; and even though the fleeting Marie forgave him, offering nothing but the purest form of encouragement, Gabriel was left broken and alone, his future in flux.

Sometime after his destruction of the Lords of Shadow, he answered the telepathic distress call of Laura, whose cries led him back to the Bernhard's former haunt. It was there that she explained to him the unintentional fallout from the Lords defeat: She explained that his vanquishing the Lords of Shadow resulted in the unleashing of a greater evil--a powerful demon that knew no pity or mercy and was bent on destroying the world. Before the Lords of Shadow came to be, there was a fierce battle where they currently stood; the three founding members of the Brotherhood fought a creature called the Forgotten One, which had been summoned by the evil Bernhard family, who at the time owned the castle. Things went badly for the Brothers, as the Forgotten One escaped its bonds; as a last-ditch effort, they used their combined powers to imprison it within a dimensional rift and constructed several seals to keep it locked in. Though Gabriel was reluctant to act, claiming to have lost his humanity, he gave in to guilt and joined Laura in the quest to destroy the Forgotten One. They scoured the castle depths in search of the founders' original tower, which housed a magical clock that was capable of rewinding time; the dimensional-rift portal stood atop the tower, but it was inaccessible due to the structure's severe deterioration, which required traveling back to the past when it was solidly constructed.

Atop the tower, they used three blood orbs, which contained the life fluids of the founders, to activate the portal. Gabriel demanding that Laura stay behind, but she blocked him from entering, warning that only dark beings could survive on the other side. Gabriel already considered himself a dark shadow, but Laura countered that he also espoused love, compassion and tenderness. To enter the portal would require that he leave it all behind and become a "creature" like her. She sliced open her wrist and asked him to drink from of the dripping entrails; the blood, she claimed, had the power to protect him once he reached the other side. He had no choice--he never did. He ingested her blood and keeled over in pain, informed that the powerful poison would soon kill him; if he wanted to remain alive, she explained, he would have to continue drinking until all of his blood was replaced with hers. She had lived many lifetimes and killed many victims, and all of her power would now be his. His hesitation pained, he'd have to follow through or die. She begged him to free her from a miserable existence, which he obliged, biting into her neck and draining every ounce; she was thus obliterated, her blood living on through the newly cursed Gabriel, who could now enter the portal.

Gabriel entered the portal and arrived at the underworld prison, where he hunted down the Forgotten One, who was close to escaping; he battled the mighty demon and did his best to thwart its vengeful march. The encounter wore him down, and the Forgotten One was ready to exit after destroying a final seal. Powered by rage, Gabriel dove toward the eroding seal and absorbed the demon's destructive essence, cutting off its escape. Devastated by the act, the Forgotten One slammed its fist into the ground but quickly accepted the reality of the situation. It turned to the enchanted, now-hovering Gabriel and said to its new master, "I yield to you. Mercy, my liege. Mercy..." No longer capable of such emotion, the all-powerful Gabriel tore the demon in half, ending its existence. As he stood there, staring into the open seal, he gripped the Combat Cross so tight that it shattered to pieces, the weapon no longer of any use to him. After a moment of eerie silence, he finally exited the prison, escaping through the seal as a new threat mankind.