Reasons were that there were a number of names (personal or locational), expressions or tales that were explained in Japanese language rather poorly. Traditional explanations were inevitably/understandably confined within the realm of the Japanese language, which had certain limitations. Indeed, IF there were contents that had a base in Jomon language, explanations thereof should be based on the Jomon language.

There is no such entity as Jomon language established such as by a dictionary. The Jomon era has been considered ended in the 3rd century BC (BC3c), when overseas invaders rushed into Japan to start the Yayoi culture. The current Japanese language clearly stems out from an old Japanese language as practiced in the 8th century AD. A likelihood is that the old Japanese has some relation with a language practiced in the Yayoi period, BC3c through AD3c.

My proposed finding is that the old Japanese language was also contributed by the Jomon language. The Jomon would not have finished in one day in BC3c in the entirety of Japan archipelago. Jomon language would have been retained by people that evaded from the invaders.

The Jomon language is proposed to have continued practiced by people who fled from the invading pressures, to have become the Ainu language eventually. In the process, the old Japanese would have adopted some of the Jomon traditions, such as place names, person names, stories and expressions.

If a baby was born between a person in the invading group and a Jomon person, the baby would have heard stories told by his/her grandparent in Jomon language. The baby, as he/she grew, would tell the story in a new language, perhaps a mix of Jomon and invading peoples' languages. Thus, there would have been some mode of translation.

An example is this. The story of a White Rabbit in Inaba.

An old rabbit in Inaba country was pushed by a flood from his place to an ocean island. In an attempt to come back to his original place, the rabbit asked sharks to align between the island and a shore nearby his place, saying "I shall count the number of your family." As the rabbit steps on the back of the sharks back to the shore, he laughed at the sharks saying that it was a lie to count the number.

This story above, of which ending part was left omitted here, as read in English (as translated by me from Japanese) would communicate basic facts, just like it is told in Japanese. However, if this story is reconstructed in Ainu which I consider is a descendent language of Jomon language, it will revive perhaps an original word-playing or association for ease of oral communication. That is

Similar to above, I have collected a number of old stories that tell more or clearer background of the stories if told in Ainu, and presented in the Japanese section of my site. Another tale added, accessible by clicking here.