How does the author use the prologue in the way to rainy mountain?

The author wanted to introduce the book’s background and his purpose for writing.

Explanation:

N. Scott Momaday's memoir "The Way to Rainy Mountain" is a form of travelogue as well as a historical documentation of his attempt to trace his heritage. It also serves as a way of reconnecting to his past, his heritage and his background.

In the prologue, Momaday begins with the description of the mountain and how it had actually been called that. The prologue also gave an introduction to why he was writing this piece, and why he needed to focus on that. Attempting to preserve the traditions and customs of his Kiowa people, Momaday relies on the prologue to give that purpose, focusing on the importance and greatness of the Kiowa people.

i would say that these are the two thesis statements best for a literary analysis essay on recurring themes in shakespeare's romeo and juliet:

1.  in romeo and juliet, shakespeare demonstrates that love comes in a variety of forms, be it romantic, familial, or between friends.

2.  shakespeare explores the struggle for identity through the character of juliet in his play romeo and juliet.

the other theses aren't reoccurring in this play. 

explanation:

"it's more of an essay than story, but perhaps it is best described as a mood-piece: it uses a lot of musical imagery, not to mention sea imagery, religious imagery, and any other imagery that suits his purpose."