A memoir is known to be only experiences that's based on its writer in terms of what they can remember during that time. Therefore, you cannot say that this is not totally related to past events in history, but rather past experiences that a person that might be in history has remembered.
In Native American literature, the following characteristics are valued;
I. Hero Initiation
II. Trickster; to reinforce the fact that we have human flaws
III. Symbolic Landmarks; relates human characteristics and emotions to geography and topography
IV. Mythology
V. Oral Tradition
These cultural beliefs held by the native Americans will inevitably hinder their relations with the European settlers as the Europeans might view their traditons as a culture shock; they have never seen such a group with ostracised beliefs.
D, to persuade readers to adopt an author's suggested course of action.