His rejection of the demands of William Yancey led to a split in his party.   
To many critics his most important writing was the essay The Dividing Line Between Federal and Local Authority.  His rejection of the demands of William Yancey led to a split in his party.   The author of the sections of the Compromise of 1850 relating to the governments of the Kansas and New Mexico territories, he created the famous "Freeport Doctrine" annunciating his theory of popular sovereignty during his run for senator in 1858.  For 10 points, name this "Little Giant," who authored the Kansas-Nebraska Act and defeated Abraham Lincoln after a series of famous debates.
To many critics his most important writing was the essay The Dividing Line Between Federal and Local Authority.  
Stephen Douglas