How does the author use imagery and dialogue to reveal Arnold Friend

Hillenbrand writes, "as louie blazed through college, far away, history was turning" (p. 43). why does the author interrupt louie's narrative with information about japan and germany?

Ipronounced his name, offering him at the same time my hand: he took it, smiling and saying, “we shall do very well by-and-by.” then he laid me down, and addressing bessie, charged her to be very careful that i was not disturbed during the night. having given some further directions, and intimates that he should call again the next day, he departed; to my grief: i felt so sheltered and befriended while he sat in the chair near my pillow… (chapter 3) this passage, in which jane first meets the doctor, is an example of

Analysis that compares and contrasts the way two myths show one important feature of their culture