Lincoln's Evolving Thoughts on Slavery, And Freedom : NPR: In 1854, Sen. Stephen Douglas forced the Kansas-Nebraska Act through Congress. The bill, which repealed the Missouri Compromise of 1820, also opened up a good portion of the Midwest to the possible expansion of slavery.
Douglas' political rival, former Illinois Congressman Abraham Lincoln, was enraged by the bill. He scheduled three public speeches in the fall of 1854, in response. The longest of those speeches — known as the Peoria Speech — took three hours to deliver. In it, Lincoln aired his grievances over Douglas' bill and outlined his moral, economic, political and legal arguments against slavery.
But like many Americans, Lincoln was unsure what to do once slavery ended.