He was born on November 14, 1374. When he was alive, Tokagero was a thief that was born into poverty.
Tokagero was forced to eat his own dead mother to survive. He then became a thief ambushing people. An ancient bandit, he stole everything--money, food, lives and even more so. He led a horde of bandits who terrorized the area 600 years ago.
There was a hill Tokagero and his group used as a hideout, but one day Amidamaru passed by and was ambushed by them. However, being the stronger one, Amidamaru killed Tokagero and his group.
Tokagero, who is created by Hiroyuki Takei, has no information regarding any inspiration used to create him. His Japanese voice actor is Wataru Takagi, and his English actor is Wayne Grayson. He first appears in Shaman King volume 3 and episode 11.
After witnessing Yoh's kindness, Tokagero cannot kill him to exact revenge. He has lost his ambitions for revenge and return to Bokuto No Ryu because he has no place to go. Ryu becomes Tokagero's friend due to their similar backgrounds.
NOTE: The information below is manga only info since the anime has diverted from the manga storyline. See anime differences under "anime and manga differences" paragraph.