http://en.wikipedia.org/wiki/Know_Nothing"The Know Nothing movement was a nativist American political movement of the 1840s and 1850s. It was empowered by popular fears that the country was being overwhelmed by Irish Catholic immigrants."..."Mainly active from 1854 to 1856, it strove to curb immigration and naturalization, though its efforts were met with little success."..."(T)he (membership was) largely middle-class and entirely Protestant."
"In California in 1854, Sam Roberts founded a Know-Nothing chapter in San Francisco. The group was formed in opposition to Chinese and Chilean immigrants as well as Irish, who had come to work in gold mines. In spring 1855, Levi Boone was elected Mayor of Chicago for the Know Nothings. He barred all immigrants from city jobs. Statewide, however, Republican Abraham Lincoln blocked the party from any successes."
"Few Know-Nothings were wealthy:
most were workers or small farmers whose jobs or ways of life were threatened by the cheap labor and unfamiliar culture of the new immigrants. Know-Nothings scored startling victories in northern state elections in 1854, winning control of the legislature in Massachusetts and polling 40 percent of the vote in Pennsylvania. Although most of the new immigrants lived in the North, resentment and anger against them was national..."
"The term "Know Nothing" is better remembered than the party itself. In the late 19th century, Democrats would call the Republicans "Know Nothings" in order to secure the votes of Catholics. Since the early 20th century,
the term has been a provocative slur, suggesting that the opponent is both nativist and ignorant. In 2006, an editorial in the The Weekly Standard by William Kristol attacked populist Republicans for not recognizing the danger of "turning the GOP into an anti-immigration, Know-Nothing party."<9> The lead editorial of the New York Times for Sunday, May 20, 2007, on a proposed immigration bill, referred to "this generation's Know-Nothings...."<10>"
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Modern "Know Nothings" aren't as anti-Catholic as the 19th century's version which combined nativism and opposition to Catholicism. The modern Know Nothings (the repubs' DLB base) are as anti-immigrant as their predecessors, but add racism to the mix in place of a fear of Catholics, IMHO.