Nativists were people who
1) Disliked immigrants- Nativists are individuals who dislike immigration for several different reasons. For one, these individuals feel threatened by immigrants. During the late 19th century in the US, immigrants from countries (like Ireland) would come to America and would often get factory jobs. These immigrants were often willing to work for less than native born citizens, causing issues between the two groups.
2) Used their animosity towards immigrants to create a political party- The Know Nothing Party of the 1800's was one that was constantly involved in actions that harmed immigrants or prevented them from expressing their voices in American society.