By 1856 Abraham Lincoln had concluded that the Whig Party was collapsing as national and Illinois politics were thrown into turmoil by the 1854 Kansas-Nebraska Act, which repealed the 1820 Missouri Compromise and opened federal territories north of its line to the possible spread of slavery through voting. On February 22, 1856, Lincoln attended an Anti-Nebraska Editors Convention at the Cassell House in Decatur, Illinois, where he was the only politician among Illinois newspaper editors opposed to the act. The convention favored restoring the Missouri Compromise and restricting slavery to its then authorized limits. Those principles guided a second convention in Bloomington that May, where the Republican Party was formally established in Illinois with Lincoln as its acknowledged leader. The struggle grew out of Lincoln's political crossroads as former Whigs faltered, Stephen A. Douglas pressed his doctrine of popular sovereignty, and Lincoln moved away from a fading party system toward new political alignment.