The addition of territory through war with Mexico inflamed slavery/antislavery tensions, resulting in the Compromise of 1850, which was an attempt to delay impending national crisis. By the Compromise, California was admitted as a free state, the territories of New Mexico and Utah would decide the slavery question for themselves upon admission to the Union, the boundary between Texas and New Mexico was established, and the slave trade was abolished in Washington, D.C. The Compromise of 1850 also included the Fugitive Slave Law, which required the return of runaway slaves to their owners. Many Northerners were furious over and unwilling to obey the Fugitive Slave Law.
Kansas was a hotbed of conflict following the Compromise of 1850. For a time, it had two governments, one that permitted and one that outlawed slavery. In this unsettled atmosphere, lives and property were lost. John Brown moved to Kansas in 1855. He became captain of a company formed to maintain Kansas as a free state, employing radically militant methods of achieving this end. (Brown led the ill-fated raid on the federal arsenal at Harper's Ferry, West Virginia, in 1859, for which he was executed.) In 1857, Kansas elected a free state legislature. It was not admitted to the Union until 1861.
The 1857 Supreme Court decision in the Dred Scott case further divided North and South. In deciding the slave Dred Scott's claim to freedom, the Supreme Court ruled that slaves could not sue because they were not citizens, and further pronounced that Congress could not prohibit slavery in territories, thereby declaring the Missouri Compromise of 1820 unconstitutional. Northerners were once again outraged. This long series of conflicts led to and was finally resolved by the Civil War (1861–1865).
