He was originally killed by Akemi, his daughter.
As he is dead, Xena had to be dead herself to fight him. She asked a samurai, Morimoto, and his army to kill her so that she can defeat Yodoshi.
Once Yodoshi had been slain, Xena released the 40,000 souls that she condemned to eternal torment but had to stay dead for them to be free. For Xena, this was the ultimate redemption, the one thing that she had wanted since she met Gabrielle.
Yodoshi was originally a Japanese Daimyo (Lord) and father of Akemi. His daughter was kidnapped at an undisclosed time by a chinese warlord and taken to a chinese fortress where she met Xena. The Warrior Princess returned her to her home with ransom in mind, but Akemi disguised herself as a performer and murdered her father as revenge for the deaths of her Grandparents, Mother and siblings. Still harboring negative feelings,the underworld refused to let Yodoshi enter the underworld. Yodoshi's spirit returned as an immortal Yokai-Daimyo (demon lord) just in time to capture the souls of the 40,000 killed in the fire a drunk and grief stricken Xena set upon Higuchi accidentally as she fought off attackers who ultimately caused her to spill Akemi's ashes, which, in turn allowed Yodoshi to capture his daughter's soul.
Yodoshi appears as a regal looking Japanese man, with Green and Magenta patterned skin: which was originally intended to be make-up, as Rob Tapert has stated he wished he "hadn't given him that make-up" because it took all the humanity from the character.