In the United States immigrant communities became a larger political influence in the early 19th century because of their dramatically increasing numbers. There were a large number of Irish and German immigrants coming to the US at this time due to famine in Ireland and political persecution in Germany. In response to the large influx of immigrants and their potential to influence the political system different groups of Americans took on anti-immigrant or "nativist" views, being strongly against the influx of immigrants and feared that these new immigrants would take their jobs. In response the Know-Nothing Party was formed to opposed this increased immigration politically.
Between 1820 and 1850, the foreign-born population growth influenced American political life, with immigrants often aligning with the Democratic Party. Nativist sentiments led to movements and laws aimed at restricting immigration, embodied in legislation such as the Alien Act, the American Protective Association's activities, and the Chinese Exclusion Act. ;
From 1820 to 1850, significant immigration from Ireland and Germany transformed the foreign-born population into a major force in American politics, raising fears among some native-born Protestants. Groups like the Know-Nothing Party emerged in response, viewing immigrants as an 'alien menace' and advocating for anti-immigrant policies to preserve their political influence. This period was marked by a blend of increasing immigrant political activity and rising nativist sentiments, leading to confrontations rooted in cultural differences.
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