During the 1830s and 1840s, what were people called who were opposed to immigration

they were treated very badly. they were targeted by white supremacists and other groups, like the klu klux klan, even after coming back to the country as veterans. they were seen as inferior and gave the african americans new found motivation to fight against this racial injustice. 

one of the main reasons was definitely slavery. back in 1861, republican abraham lincoln was elected and ended up being a major influence in the slavery business. slavery greatly affected the texas economy because back in 1845 during the annexation of texas, slaves became a big part of the texas population. many texans that were in favor of the secession influenced groups through party ties.