Tsukayama Yuzaemon was a low-ranked samurai whose position changed drastically after the events of the bakumatsu. With the samurai class all but disbanded, Yuzaemon became a merchant specializing in the sale of Japanese katana as art to foreign buyers. His business became profitable and allowed him and his son Yutarō to become independently wealthy and move to a large estate outside of Tokyo.
However, Yuzaemon secretly viewed his life of servility as one of failure, having given up his pride for money, and hoped that Yutarō would grow up stronger than he had been. Unfortunately, his successes also drew unwanted attention when a group of bandits attacked the Tsukayamas' carriage during a night ride. As Yuzaemon begged fruitlessly for his life, he and his son were suddenly saved by the timely intervention of passing swordsman Isurugi Raijūta. Realizing his helplessness in the face of violence, Yuzaemon asked Raijūta to stay at his mansion with the purpose of teaching Yutarō kenjutsu in exchange for funding the swordsman's own small kenjutsu school of Shinko-ryū.
For roughly three months, Raijūta remained at the mansion and Yutarō remained at the swordsman's side as his pupil and ward; however, when Raijūta encountered another swordsman named Himura Kenshin, a fight broke out between them and young Yutarō was grievously injured by Raijūta's carelessness, losing the use of his right arm.
Realizing his mistake in trusting Raijūta and feeling responsible for the death of Yutarō's kenjutsu dreams, Yuzaemon decides to move his son to Germany where advanced Western doctors may find a way to heal his son's arm.
In the anime, Yuzaemon had died some time before Yutarō's introduction. This version of Yuzaemon is also quite wealthy and leaves his son a large fortune, but is remembered as a particularly strong warrior, motivating Yutarō to follow in his father's footsteps rather than distinguish himself from his parent's legacy.