In June 1858, fol­low­ing James Hammond’s depar­ture from Wash­ing­ton, Abra­ham Lin­coln cap­tured atten­tion at the Repub­li­can Illi­nois State Con­ven­tion by secur­ing the nom­i­na­tion for the U.S. Sen­ate. Aged forty-nine, Lin­coln was set to face the younger Demo­c­ra­t­ic incum­bent, Stephen Dou­glas. Their com­pe­ti­tion fos­tered sig­nif­i­cant inter­est, espe­cial­ly giv­en their con­trast­ing phys­i­cal presences—Lincoln’s height of six-foot-four sur­pass­ing Douglas’s stature sig­nif­i­cant­ly.

Dur­ing the con­ven­tion clos­ing, Lin­coln deliv­ered a pow­er­ful, albeit poten­tial­ly polit­i­cal­ly detri­men­tal, address posi­tion­ing him­self firm­ly against slav­ery. His law part­ner, William Hern­don, acknowl­edged the speech’s moral valid­i­ty but ques­tioned its polit­i­cal pru­dence. In this address, Lin­coln crit­i­cized Douglas’s Kansas-Nebras­ka Act, claim­ing it esca­lat­ed the dis­cord con­cern­ing slav­ery that the Mis­souri Com­pro­mise had tem­porar­i­ly quelled. He declared that a major cri­sis loomed, allud­ing to the bib­li­cal adage, “A house divid­ed against itself can­not stand.” Lin­coln argued that the gov­ern­ment could not endure as half slave and half free.

Express­ing his hopes, Lin­coln artic­u­lat­ed a desire to halt slav­ery’s expan­sion rather than abol­ish it out­right. He envi­sioned a future where pub­lic sen­ti­ment would lean towards its grad­ual extinction—however, he assert­ed that Dou­glas’s leg­is­la­tion made this increas­ing­ly unat­tain­able. He con­clud­ed his speech with a spir­it­ed con­fi­dence in the Repub­li­can Party’s strength, for­ti­fy­ing belief in their even­tu­al tri­umph against the pro­po­nents of slav­ery.

Despite ulti­mate­ly los­ing the elec­tion, Lin­col­n’s nation­al pro­file surged, and the “house divid­ed” phrase became a prophet­ic echo of the divi­sions to come in the nation.

In the months that fol­lowed, anoth­er promi­nent fig­ure, Sen­a­tor William H. Seward, spoke pow­er­ful­ly against slav­ery. In an Octo­ber speech in Rochester, New York, he echoed Lin­col­n’s warn­ings but went fur­ther, sug­gest­ing that the sys­tems of slav­ery and free labor were fun­da­men­tal­ly incom­pat­i­ble. He framed the strug­gle as an “irre­press­ible con­flict,” argu­ing that the Unit­ed States would even­tu­al­ly become either entire­ly slave­hold­ing or entire­ly com­mit­ted to free labor. Assert­ing that the Demo­c­ra­t­ic Par­ty was fun­da­men­tal­ly aligned with slave­hold­ers, Seward empha­sized the ongo­ing rev­o­lu­tion against slav­ery in the Unit­ed States. His address intro­duced piv­otal phras­es that would shape the polit­i­cal debate in the years ahead, solid­i­fy­ing the con­cept of an “irre­press­ible con­flict” in the nation­al con­scious­ness.