Life in America during the mid 1800's was very complex. On one hand you have free and enslaved blacks constantly facing prejudice and discrimination in American society. Politicians all over the South used their best persuasion skills to convince white Southerners that blacks were inferior to whites as a means to justify the institution of slavery.
Also happening in America during this time was a huge amount of immigration from countries like Ireland. The Great Famine in Ireland that took place during the 1840's resulted in a huge amount of emigrants (people moving to another country to live there permanently) greatly increased the population of the North. Despite this increase in population, there were still many American citizens who were anti-immigration. This group was known as nativists. These nativists feared that immigrants would come into America, take jobs from American citizens, and would try to change the values of America.