I think the main point of The river Between is how some cultural differences between people can create major rifts between civilizations. On the one side of the river the story is based on two people from each tribe falling in love and finding ways to make their love work even though neither are accepted by the other's tribe. A girl, Nyambura, is from the tribe of Makuyu and they believe in the religion of Christianity in addition to being against the practice of circumcision. The boy, Waiyaki, from the tribe of Kameno on the other side of the river that believes in Polytheism and believe in circumcision. This is a very sacred tradition for this tribe and they believe that you cannot become a man until you have been circumcised. This part of the story is the main part of the book and the two trying to find possible ways to make their relationship work even though they are not accepted by either tribe. When Waiyaki asks nyambura to marry him, she tells him how her father will never allow it and that it will never be able to work between the two. This book shows that differences in cultures can create awkward circumstances.