The main attitudes that seem pervasive in rural Southern Maycomb are racism and prejudice against different social classes.
The elements of setting that are most significant here are historical context and local customs. The time the story took place, in the 1930s, and the practices of the South, had an impact on the story.
All of these elements are present in the first few chapters.
The first distinction we are introduced to is class distinction. Walter Cunningham, Scout’s classmate, comes to school without a lunch. His teacher, Miss Caroline, tries to give him money to buy lunch. He refuses, because he does not have any way to pay it back and his family is too proud to take charity.
Since their father is a lawyer and they belong to a good family, Jem and Scout are not really poor. However, they don’t have gobs of money either.
Atticus said professional people were poor because the farmers were poor. As Maycomb County was farm country, nickels and dimes were hard to come by for doctors and dentists and lawyers. (ch 2)
People will not look down on the Finches, because they come from a good family. Atticus tries to tell the children that their aunt wants them to act as respected citizens.
[You] are not from run-of-the-mill people, that you are the product of several generations' gentle breeding… and that you should try to live up to your name. (ch 13)
In Maycomb, family is everything. Tradition, and the value of one’s family name, dictates who you are.
Aunt Alexandra was of the opinion, obliquely expressed, that the longer a family had been squatting on one patch of land the finer it was. (ch 13)
Thus, people are known by their “clan” of Finches, Ewells, Cunninghams and so on. As a family they are expected to share similar traits. People don’t rise above their family.
The other key attitude is people’s feelings toward race. There is rampant racism in Maycomb. In fact, it is not considered proper to not be racism. When Scout gets in fights for defending her father, he tells her that there is nothing wrong with being black.
I'm simply defending a Negro- his name's Tom Robinson. He lives in that little settlement beyond the town dump. He's a member of Calpurnia's church, and Cal knows his family well. (ch 9)
The people of Maycomb refuse to accept that Robinson might be innocent, or even that he deserves a fair trial. They treat all non-whites as second-class citizens who are inferior because of their skin color. Atticus is one of the few who does not think this way.
The significant elements of setting are historical context and local customs. Because of the time and local customs, race and social class were crucially important to characters.