The Lincoln-Douglas debates happened outside of Quincy.
The Lincoln -- Douglas Debates ( also known as The Great Debates of 1858 ) were a series of seven debates between Abraham Lincoln , the Republican candidate for the United States Senate from Illinois , and incumbent Senator Stephen Douglas , the Democratic Party candidate . Because both had already spoken in two -- Springfield and Chicago -- within a day of each other , they decided that their `` joint appearances '' would be held only in the remaining seven districts . The debates in Freeport , Quincy and Alton drew especially large numbers of people from neighboring states , as the issue of slavery was of monumental importance to citizens across the nation . The widespread coverage of the original debates and the subsequent popularity of the book led eventually to Lincoln 's nomination for President of the United States by the 1860 Republican National Convention in Chicago .