The north and the south differed in a couple of ways in the mid 1800's, economically and socially which contributed to a rise of regional populations with contrasting values, ideologies and visions for the future. The differences includes; vast industry and immigration in the north, established agriculture in the south and slave trade carried out in the south.
Hundreds of Indian peoples, tribes, languages, and ways of life" would be the best option from the list, since the native population of the United States was incredibly diverse.
They are called historians lol
They discover, study, interpret and write HISTORY, so they are historians!
