Political doctrine that allowed the settlers of U.S. federal territories to decide whether to enter the Union as free or slave states. It was applied by Sen. Stephen A. Douglas as a means to reach a compromise through passage of the Kansas-Nebraska Act. Critics of the doctrine called it “squatter sovereignty.” The resulting violence between pro- and antislavery factions (see Bleeding Kansas) showed its failure as a workable compromise. Seealso Dred Scott decision.

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