be decided. Both sides were anxious about effects of these decisions on the balance of power in the Senate. After the passage of the Kansas–Nebraska Act in 1854, border fighting broke out in the Kansas Territory, where the question of whether it would be admitted to the Union as a slave or free state was left to the inhabitants. Migrants from both free and slave states moved into the territory to prepare for the vote on slavery. Abolitionist John Brown, the most famous of the anti-slavery immigrants, was active in the fighting in "Bleeding Kansas," but so too were many white Southerners (many from adjacent Missouri) who opposed abolition. Abraham Lincoln's and the Republicans' political platform in 1860 was to stop slavery's expansion. Historian James M. McPherson says that in his famous "House Divided" speech in 1858, Lincoln said American republicanism can be purified by restricting the further expansion of slavery as the first step to putting it on the road to 'ultimate extinction.' Southerners took Lincoln at his word. When he won the presidency, they left the Union to escape the 'ultimate extinction' of slavery." Freedom suits and Dred Scott With the development of slave and free states after the American Revolution, and far-flung commercial and military activities, new situations arose in which slaves might be taken by masters into free states. Most free states not only prohibited slavery, but ruled that slaves brought and kept there illegally could be freed. Such cases were sometimes known as transit cases. Dred Scott and his wife Harriet Scott each sued for freedom in St. Louis after the death of their master, based on their having been held in a free territory (the northern part of the Louisiana Purchase from which slavery was excluded under the terms of the Missouri Compromise). (Later the two cases were combined under Dred Scott's name.) Scott filed suit for freedom in 1846 and went through two state trials, the first denying and the second granting freedom to the couple (and, by extension, their two daughters, who had also been held illegally in free territories). For 28 years, Missouri state precedent had generally respected laws of neighboring free states and territories, ruling for freedom in such transit cases where slaves had been held illegally in free territory. But in the Dred Scott case, the Missouri Supreme Court ruled against the slaves. After Scott and his team appealed