Following the Kansas-Nebraska Act of 1854—which permitted Kansas to allow or reject the institution of slavery by popular sovereignty—a destructive and sometimes bloody border war between Kansas and Missouri partisans raged for six years.
In 1860, about 80 percent of Missouri’s population was made up of first or second generation immigrants from other Southern and Border States, but only 13 percent of Missouri households owned slaves. Except for St. Louis, a city of 160,000, where new German immigrants made up a considerable portion of the population, Missouri was solidly Conservative and Democrat in its political leanings. Lincoln ran fourth in the 1860 presidential election, capturing only 10 percent of the vote.
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