Where did it come from?

Some guidance may be found in record of Japanese literature called the kojiki, or Ancient Matters record.

The kojiki describe negotiations between a race of divine origin and common race over the ownership of land.

A member of the common race, Takeminakata- Nu-Kami , dissatisfied over the result of the parle, challenged the representative of the divine race, Takemekazuchi-Nu-kami, to settle the matter by wrestling. When the challenger lost the contest, the divine race took the land, thus bringing unity to the nation. Some believe that this was the inception of sumo wrestling.

In 22 B.C another such wrestling match took place between Taima-Nu-Kami and Nomi-Nu-Sukune. The outcome was that Nomi-Nu-Sukune threw his opponent to the ground and kicked him to death.

This contest supposedly was the inception of what we now call ju jutsu.