The Lincoln-Douglas Debates were a series of seven debates held in 1858 between Abraham Lincoln and Stephen A. Douglas, who were competing for a seat in the U.S. Senate from Illinois. These debates focused primarily on the issue of slavery and its expansion into new territories, highlighting the contrasting views of the two candidates. Lincoln argued against the spread of slavery, advocating for its containment, while Douglas supported popular sovereignty, allowing territories to decide for themselves. The debates gained national attention and significantly raised Lincoln's profile, setting the stage for his later election as the 16th President of the United States.