The following recap is featured in a cutscene in the introduction of Castlevania: Lords of Shadow 2.
In ages long past, there was once a warrior who was both noble and brave beyond all measure. His deeds of heroism and skill in combat were legend. His name was whispered within the hallowed halls of men for countless generations. Yet now his name is lost, lost in the mists of time forever. It is said that destiny delights in the misfortunes of men, and so it proved true for Gabriel Belmont.
For even after defeating the Lords of Shadow and ending their reign of terror, his soul was consumed by the very darkness that he sought to destroy. As that ancient prophecy foretold, whomsoever defeats the Lords of Shadow will sit upon their throne to rule as the Prince of Darkness.
But before fate had played its hand, and unknown to Gabriel, his beloved wife Marie conceived a son by him. The Brotherhood of Light warned her of that ancient prophecy and the terrible fate which lay before her husband. So with heavy heart, she concealed her pregnancy. For it is written that only the blood of that lineage has the power to defeat the Prince of Darkness. Thus when newly born, the child Trevor was hidden from his father, and raised a holy warrior of the Brotherhood in secret so that one day he would be ready to stand against his own blood, as foretold.
That day would come, some twenty five years later. For what had once been Gabriel Belmont was now a powerful vampire known as Dracula, the Dragon. The Brotherhood of Light fought against the onslaught of his dark armies which laid waste to towns and villages across the land but to little avail. Trevor was now fully grown to manhood, and the truth of his origin and destiny of the Belmont clan was finally revealed to him. So he set out to confront his father, and end his family shame forever. But Trevor failed, and was mortally wounded in the confrontation with his father. He was no match for Dracula's terrible power. Yet as he lay dying, Trevor finally revealed his true identity. Dracula was driven mad with grief and rage over the revelation. He desperately sought to save his dying son by giving him his own lifeblood, but it was too late, or so he thought. Dracula buried his son within the walls of his great castle, and then swore bloody vengeance upon the world. Raising an army of creatures beholden only to him, he struck with fury and merciless cruelty at humanity. He vowed to hunt God's children for all eternity.
But fate still had one last card to play. Dracula's blood had power and that power now coursed through the veins of his dead son, slowly reviving him over many years, until one night, he emerged once more into the world not as a man but as a creature like his father. What had once been Trevor Belmont was now gone forever. He was now a vampire like his father though he swore that he would not be like him. He would take the name Alucard. He would be a force for good opposing his father's capacity for evil. In that very moment, Alucard swore to destroy Dracula. But fate had something else in mind.
Meanwhile, Trevor's own son grew into a fearsome warrior with a reputation that far exceeded even that of his illustrious father. Simon Belmont knew little of his own lineage, nor his importance in the events to come. All he knew was that his mother had died at the hands of Dracula's minions when he was but an infant and his father had been killed in single combat with Dracula. Found and raised by the people of White Mountains, Simon had but one purpose in life to destroy Dracula for the murder of his parents. After years of training in the arts of war, Simon set off for Dracula's castle, and a date with destiny.
Once in the castle Simon met Alucard, and knowing little of the true identity of his companion, joined forces with him. Blood bound them together and fate took a hand once again, as finally they met their dreaded foe in mortal combat. Simon defeated Dracula with his whip, and yet, Alucard sensed that all was not as it should be.
Dracula... would return.