Immortal Ritter Hans Kirshner died his first death in the year 978. His mentor was Graham Ashe who taught him about his immortality.
Kirshner was an excellent swordsman, and worked as an dueling instructor. In the 19th century, the Immortal Byron seduced his wife, infuriating him. Kirshner searched for Byron in order to exact his revenge. He found him in 1816, together with his mentor, Methos.
He challenged Byron who didn't take him seriously. Methos, however, did, and warned his pupil that he was not ready and to give way. Byron had not yet taken a head at that point. Methos then tried to reason with Kershner, but he refused to retract his challenge, he would face Byron.
Byron was no real match for an excellent swordsman like Kirshner, and after a short fight, Bryon took a fatal wound, but pulled a hidden blade from his cane and returned the favor, fatally stabbing Kirshner.
Before falling to his wounds, Byron beheaded Kirshner and took his Quickening even as he died.
Note: Kirshner was portrayed by the series fight choregorapher F.B. McAsh