Explore a comprehensive lecture from Yale University's "The Civil War and Reconstruction" course, delving into the tumultuous events of 1855-1858 that led to the impending crisis of the Union. Examine the aftermath of the Kansas-Nebraska Act, including the guerrilla warfare in Kansas and the violent caning of Senator Charles Sumner. Learn about the birth of the Republican Party and its near-victory in the 1856 presidential election with candidate John C. Fremont. Analyze the significant Dred Scott decision of 1857 and its impact on the nation. This 52-minute lecture provides a detailed chronological account of the political landscape and escalating tensions that ultimately contributed to the outbreak of the Civil War.