General Jarjayes, whose full name is François Augustin Regnier de Jarjayes, is the father of Oscar François de Jarjayes and a high-ranking general in the French royal army during the reign of Louis XVI. As the head of the aristocratic Jarjayes family, he serves as the Commander of the Royal Guards at the Palace of Versailles, a position of significant prestige and proximity to the monarchy. His most defining action is driven by his lack of a male heir; having fathered six daughters, he decides to raise his youngest child, Oscar, as if she were a son to succeed him in his military command.

General Jarjayes is a staunch royalist, characterized by an unwavering and absolute loyalty to the French crown. His personality is marked by a rigid adherence to tradition, honor, and the strict hierarchies of the aristocratic society he represents. He is a disciplinarian, especially in his training of Oscar, whom he raises with the expectation of fulfilling the family's military legacy. Despite this stern and duty-driven exterior, his motivations are deeply rooted in a paternal, albeit flawed, love. His primary motivation is to secure the future and honor of the Jarjayes name. He believes that by preparing Oscar for a military career and securing her the protection of the Queen, Marie Antoinette, he is ensuring her safety and the family's continued relevance. In his view, this path is a pragmatic solution to the impossibility of producing a male heir, driven by a parental instinct to protect his child from a world that offered few options for noblewomen.

In the story, General Jarjayes serves as a direct representation of the old aristocratic order. He is the initial architect of Oscar's unique life, personifying the rigid expectations and gender roles that she struggles against. His position as Commander of the Royal Guards is eventually passed on to Oscar, placing her at the heart of court life. His most significant relationship is with his daughter, Oscar. While he loves her, his love is conditional on her adherence to the role he created for her. He takes pride in her military accomplishments but is often baffled and angered by her growing independence and her dawning sympathy for the common people. His relationship with André Grandier, Oscar's childhood companion and eventual lover, is notably complex. Bound by class prejudices, he is furious upon discovering André's romantic love for Oscar, insisting that an aristocratic marriage requires royal permission. Yet, contradicting his own strict social code, he privately cherishes André as if he were a son and consistently assigns him as Oscar's personal guard, demonstrating a hidden affection for the young man.

His relationship with the monarchy is one of total fealty. This loyalty defines his role as the story progresses, as he remains a devoted servant to the crown even as its authority crumbles. While General Jarjayes does not undergo a fundamental change in his core beliefs, his development is seen in his growing regret and helplessness as a father. He initially rejoices when Oscar receives a marriage proposal from a fellow aristocrat, seeing it as a way to secure her future and remove her from danger. As the revolution intensifies and Oscar openly defies him by siding with the people, he experiences profound conflict. He loves Oscar but cannot abandon his principles. In a moment of extreme duress, he even attempts to kill her, believing her path to be a betrayal of everything he stands for, only to be disarmed. Near the end of his life, a glimmer of his former passionate nature appears when he joins forces with Count Axel von Fersen to attempt a rescue of the imprisoned Marie Antoinette, an act that shows his loyalty is ultimately more to the people of the royal family than to the abstract institution of the monarchy.

His notable abilities are those befitting a high-ranking general of his era. He is a skilled military strategist and an experienced commander. He is also a proficient swordsman, capable of engaging in combat, as demonstrated in his final confrontation with Oscar. Furthermore, he possesses a deep understanding of court politics and the workings of the royal military, knowledge he works to instill in Oscar from a young age. His primary power, however, lies in his authority and his name, which initially opens doors for Oscar but ultimately cannot shield either of them from the tide of revolution.