For those who have read the story and who know some American history, one can see the attention to detail the authors have put into this. We have the mad omnipotent Sun Chief, Theron, and the Warrior leader Badgertail, who obeys his commands even though he disagrees with them. The descriptions of the land make the book a good read. The many different threads that make up the story; disgruntled villages rebelling against the Sun Chief over tributes that need to be paid (main plot), the love between Badgertail and Locust, the dilemma of Badgertail with obeying Theron and doing what he believes is right, the relationship between Lichen and Wanderer, the growth of Lichen spiritually to become a powerful dreamer (subplots) and the way each are connected to one another makes the book interesting.
However, it is disappointing in the lack of character detail. (The landscape detail is excellent and so are the plot and subplots). Of all the characters in the book, only Badgertail is described somewhat fully. The reader cannot predict how a character will behave because not enough character traits are given. Because of this lack of detail, the reader cannot fully engage in the story. Some examples of fantasy novels that will pull the reader into the story are Robert Jordan's "Wheel of Time" series, George RR Martin's "Song of Ice and Fire" series and Stephen Donaldson's "Chronicles of Thomas Covenant". True all these novels are much longer than "People of the River", but nevertherless are much better reads because of the added detail. An example of a great short novel is the war story " All Quiet on the Western Front" written by Erich Maria Remarque which is much shorter than this novel but is more descriptive of its characters. A similar kind of story (historical fiction) to "People of the River" is written by Jean Auel in the "Earth's Children" series but with the character analysis far surpassing this.
Nevertheless, if all you are after is a book to fill up time, this book is not a bad one to pick. However if you want a great book, go for one of the ones I have listed. They are much more enthralling novels.