It is important to study the historical context of a piece of literature to better understand:

a. the author's use of audience appeals.
b. why the author left out certain information.
c. the fears and interests of the story's original audience.
d. the book's popularity.

anne started to write her events in her journal everyday considering it someone would find it .

well stockyards mean a large yard containing pens and sheds, typically adjacent to a slaughterhouse, in which livestock is kept and sorted. and i'm assuming that by party you   mean a large group of people which does make sense because chicago is a very crowded place much like new york. stockyards tend to take up a lot of room due to needing the area for pens to keep animals in and the fact that stockyards are usually right by slaughterhouse where they process and distribute the product. so its much like a zoo but with some dead animal products close by.