The lands added to the nation through the conquests of the Mexican War raised anew the question of whether or not slavery would be allowed to expand into the new territories of the west. For two years, opposition of many Northerners to expansion of the slave system kept Congress from organizing the newly acquired lands into territorial governments. The gold rush in California forced the issue. California's population rapidly reached 60,000, the number at which they could call a constitutional convention, organize their own government, and petition to be admitted as a state. Their new constitution outlawed slavery. Because California's admission as a free state would have upset the balance of equal numbers of free and slave states in the Senate, the South opposed its admission. The political crisis was finally resolved with the passage of the Compromise of 1850. One of the concessions for the South's approval of admission of California was the promise that a new and strict law returning all fugitive slaves would be passed and enforced. This cartoon, "A Practical Illustration of the Fugitive Slave Law," published in 1851, shows how reluctant Northerners were to enforce the law. The 1854 publication of Harriet Beecher Stowe's book, "Uncle Tom's Cabin," further inflamed Northern opinion against the law.
Courtesy of the Library of Congress.