Jonathan Joestar, born in 1868 to George Joestar I and Mary Joestar in England, lost his mother in a carriage accident during infancy. This tragedy led his father to later adopt Dio Brando out of perceived debt to Dio's father. Jonathan's childhood displayed pride, mischievousness, and gentleness as he aspired to become a "true gentleman," though peers often ostracized him due to his aristocratic status. He showed early courage defending Erina Pendleton from bullies. Dio's arrival intensified Jonathan's hardships through systematic bullying, academic rivalry, and emotional manipulation, culminating in Dio forcibly kissing Erina and killing Jonathan's dog Danny. This triggered Jonathan's first victory over Dio, during which he saw the Stone Mask react to Dio's blood. By 1888, Jonathan studied archaeology at Hugh Hudson Academy. Discovering Dio was poisoning his ailing father, Jonathan journeyed to Ogre Street. There, he confronted thugs led by Robert E. O. Speedwagon; his physical prowess and resolve converted Speedwagon into a lifelong ally. They obtained an antidote from poison supplier Wang Chan. Confronting Dio at the Joestar mansion, Dio used the Stone Mask with George's blood, transforming into a vampire. After Dio murdered George, Jonathan burned the mansion down in a battle seemingly killing Dio. Hospitalized, Jonathan reunited with Erina Pendleton, rekindling their relationship. During recovery, he met Will Anthonio Zeppeli, who explained the Stone Mask created vampires vulnerable to solar energy channeled through Hamon (Ripple) breathing. Zeppeli trained Jonathan in Hamon over approximately one week, granting him abilities like Zoom Punch (arm dislocation for extended reach) and energy projection techniques such as Sunlight Yellow Overdrive. This mastery allowed Jonathan to repel Wang Chan, now a zombie. Jonathan, Zeppeli, and Speedwagon traveled to Windknight's Lot to confront Dio, facing threats like Jack the Ripper, whom Jonathan defeated using Hamon-conductive wine as a tracking device. At Windknight's Lot, Dio deployed zombie knights Bruford and Tarkus. Jonathan defeated Bruford underwater using air bubbles for Hamon breathing, earning Bruford's sword "Luck and Pluck". Tarkus overpowered the group until Zeppeli sacrificed himself, transferring his remaining Hamon to Jonathan. Empowered, Jonathan killed Tarkus. The final confrontation occurred at Dio's castle. Jonathan fought Dio, who countered Hamon with freezing abilities. Jonathan ignited his fists to bypass freezing and delivered a decisive Hamon strike. Later, during Jonathan and Erina's honeymoon voyage, Dio resurfaced as a severed head. Attacking with eye lasers, Dio pierced Jonathan's throat, inhibiting Hamon breathing. Jonathan used his final Hamon to control a zombie, causing a ship explosion. He protected Erina and an unrelated infant by securing them in Dio's coffin as a lifeboat, remaining aboard the sinking ship with Dio. Jonathan died from his throat wound; Dio appropriated his body. Posthumously, Jonathan fathered George Joestar II with Erina before death. Dio's use of Jonathan's body later resulted in biological sons Giorno Giovanna, Donatello Versus, Rikiel, and Ungalo. His legacy persisted through descendants including Joseph Joestar (grandson) and Jotaro Kujo (great-great-grandson). An alternate universe counterpart, Johnny Joestar, appeared in Steel Ball Run. Non-canonically, a version from the 37th universe in the novel Jorge Joestar died preventing a train robbery by his universe's Dio. Physically, Jonathan stood 195 cm tall with an extremely muscular build. As a child, he wore Victorian-era jackets, breeches, and dress shoes. His adult attire reflected nobility: rugby uniforms during university, deerstalker caps and cloaks for investigations, and tunics with bowties during battles. Later adaptations added the Joestar family's star-shaped birthmark to his left shoulder. Personality-wise, he upheld ideals of gentlemanly conduct, treating others with respect unless they demonstrated evil. Key traits included fierce inner resilience termed "explosive power" by Dio, loyalty to loved ones, and mercy even toward adversaries. He studied the Stone Mask academically without discovering its true purpose. His combat intelligence allowed strategizing using environments, like deducing coal deposits beneath Windknight's Lot or igniting gloves against Dio. Abilities combined natural athleticism with Hamon mastery. Pre-Hamon, he excelled in boxing and rugby, wielded medieval weapons effectively, and demonstrated feats like jumping while impaled. Hamon techniques included energy conduction through liquids, metals, and organic materials, alongside specialized attacks like Scarlet Overdrive (fire-imbued) and Turquoise Blue Overdrive (underwater use). Posthumously, his body manifested a Stand similar to Hermit Purple when utilized by Dio.