Starting the stories with his childhood makes Ngugi's stories seem more real than others because people think that it is a real life story.Mentioning childhood invokes multiple senses of the readers,engages the readers,evokes strong emotions as people start to think of their own childhood as well, helps in creating intriguing and complex characters for Ngugi's stories,the writer may use rich character voice,Ngugi is able to pull his readers into action.
The most obvious reason is that one has to pack up and go because things are not so good at home. Long ago, that probably meant that the climate had changed and made life impossible. It might have become too hot or too cold or too wet, which in turn would have affected not only quality of life but also make survival a shaky proposition. Drought, flood, and temperature changes could certainly push people to move on.
I hope that helped a little.
It is called a Referendum
hope this helps
