The excitement produced by the repeal of the Missouri Compromise in 1854, by the election forays of the Missouri Border Ruffians into Kansas in 1855, and by the succeeding civil strife in 1856 in that Territory, wrought an effective transformation of political parties in the Union, in preparation for the presidential election of that year.  This transformation, though not seriously checked, was very considerably complicated by an entirely new faction, or rather by the sudden revival of an old one, which in the past had called itself Native Americanism, and now assumed the name of the American Party, though it was more popularly known by the nickname of “Know-Nothings,” because of its secret organization.  It professed a certain hostility to foreign-born voters and to the Catholic religion, and demanded a change in the naturalization laws from a five years’ to a twenty-one years’ preliminary residence.  This faction had gained some sporadic successes in Eastern cities, but when its national convention met in February, 1856, to nominate candidates for President and Vice-President, the pending slavery question, that it had hitherto studiously ignored, caused a disruption of its organization; and though the adhering delegates nominated Millard Fillmore for President and A.J.  Donelson for Vice-President, who remained in the field and were voted for, to some extent, in the presidential election, the organization was present only as a crippled and disturbing factor, and disappeared totally from politics in the following years.

Both North and South, party lines adjusted themselves defiantly upon the single issue, for or against men and measures representing the extension or restriction of slavery.  The Democratic party, though radically changing its constituent elements, retained the party name, and became the party of slavery extension, having forced the repeal and supported the resulting measures; while the Whig party entirely disappeared, its members in the Northern States joining the Anti-Nebraska Democrats in the formation of the new Republican party.  Southern Whigs either went boldly into the Democratic camp, or followed for a while the delusive prospects of the Know-Nothings.

This party change went on somewhat slowly in the State of Illinois, because that State extended in territorial length from the latitude of Massachusetts to that of Virginia, and its population contained an equally diverse local sentiment.  The northern counties had at once become strongly Anti-Nebraska; the conservative Whig counties of the center inclined to the Know-Nothings; while the Kentuckians and Carolinians, who had settled the southern end, had strong antipathies to what they called abolitionism, and applauded Douglas and repeal.