Yoh was born in the year of 1985, on May 12th, to Mikihisa Asakura and Keiko Asakura, and spent most of his early years in Izumo, Japan, with his mother, grandfather, and his young apprentice, Tamao, who raised him in the ways of the shaman. Because of his heritage, Yoh's childhood was rather lonesome, and he barely had any friends other than the spirits who lived with him. He was usually alienated by normal people because of his powers, and so he spent most of his time alone with the orange set of headphones he took from his father.
Even though life looked grim for him, he maintained a positive outlook and envisioned a better life for himself; one that's carefree, easy, and fun, where he's free to be lazy and slack off all he wants without being outcast for who he is. This was his prime motivation for becoming Shaman King, which he developed at age 4 when his grandfather told him the story of the Great Spirit. He trained from that day on, and at age 10, was told of his engagement to Anna Kyoyama, a Spirit Medium. On this day, he was also given his first Guardian Spirit, Matamune - a cat spirit who had served the Asakura family for over a thousand years. This spirit became Yoh's escort to Ozorenzan, where he was to meet his fiancée.
Upon traveling there, Yoh met a girl, and they were both attacked by an Oni on the streets, which Matamune protected them from. The two eventually arrived at Yoh's grandmother's home, where he was introduced to his fiancée, who turned out to be the girl from before! Although he made an effort to hide it, meeting Anna was love at first sight for him, as he slowly began to realize the powers that she truly possesses as a Reishi. This gave him another motivation to become Shaman King: so he could take Anna as his queen, and allow her to live an easy life as well.
Yoh eventually moved to Funbari Hills in Tokyo to find a main guardian spirit for the upcoming Shaman Tournament that would be held there. A tournament that is held every 500 years; a battle between shaman to crown a winner known only as the Shaman King. The Shaman King has the ability to reshape the world as he or she chooses, and Yoh planned to make life easy.
Along the way, Yoh meets many different shamans and spirits whom he befriends, and though things start out as a simple means of achieving peace and freedom in the world, it soon changes drastically into a battle of destiny where Yoh must realize his fate and save the world from his twin brother, Hao Asakura, who is the reincarnation of one of the greatest shaman to ever live, and his plan to become Shaman King and annihilate all of humanity, leaving only the shaman race.