Like many cultures, the Ainu people are some that believe in many cosmos or beliefs. There are specific beliefs that are directly from their culture, in which not one other tribe is similar to them. One of these myths or cosmology of the Ainu is the creation of their people:
This belief is that there contains of six heavens and six hells in which there is said to have gods, demons, and animals live. In the lower of the heavens is where the demons lived. Where the stars and sky are is where the “lesser” gods lived. In the highest of the heavens is where Kamui lives, whom is the created God, and also his servants reside. Kamui made his own world in which the only entry was through a giant metal gate. His realm was surrounded by water and located this world on the backbone of a humongous trout. One day he looked down upon this world and wanted to make something of it. He decided to send a water wagtail to create this land, in which the wagtail did so under Kamui’s orders. With the wings and feet of this wagtail was patches of land created and animals saw how tremendously beautiful this land was and so insisted to live on it. They asked Kamui and he responded yes to these animals. But Kamui had plans for other creatures to live there, in which were the Ainu people. These were the first people to live there and he sent down a man to teach these people how to cook and hunt.

This above myth was only one of the myths that is said about the creation of the Ainu people.
Another belief that the Ainu have is about the bear specifically. A very important god to them is the god of bears and mountains. The Ainu people believe that animals are severely important to them, but the bear especially is important. The bear, in fact, is said to be the head of gods. It is also known as kamuy or “God.” It is traditional for the Ainu people to sacrifice bears in order to release the God in them to the world of spirits. For example, the Ainu people would raise a bear cub, similar to that of a child, until it is of a certain age and then sacrifice it. This was known as lotame.

A third belief that the Ainu have is the belief that even after death everyone and everything still interact for the rest of time. It is said that both worlds are mutual and any person or anything can visit either of the two worlds. They can switch places if they would like as well. When one would visit the other, these trips occurred in dreams. These visits were encouraged mainly toward the deceased.
Pictures: http://www.read-legends-and-myths.com/ainu-creation-myth.html
http://www.actionagainstpoisoning.com/CRY%20FOR%20HELP/JAPAN%20BEAR%20RITUAL/CRYJAPANBEARRITUAL.html