President Abraham Lincoln’s Emancipation Proclamation, issued on January 1, 1863, was a war measure ending slavery where the rebellion was still operative. Questions remained about whether emancipation accomplished through this war measure would last beyond the war. The Constitution, after all, left the states the power to decide whether or not to adopt slavery. This left open the possibility that defeated rebellious states could reenter the Union without giving up slavery. Republicans opposed such a result as a betrayal of the Union’s war aims. Attention thus turned to amending the Constitution as a means of accomplishing emancipation. The model for the wording of the 13^th Amendment was the Northwest Ordinance of 1787, which prohibited slavery from spreading into the free territories of Indiana, Michigan, Wisconsin, Illinois, and Ohio. The Senate approved what became the 13^th Amendment in April 1864 by an overwhelming margin (38-6), but in June 1864 the House fell 13 votes shy of the necessary 106 votes to submit the amendment to the states. Meanwhile, border states such as West Virginia and Maryland and formerly rebellious states such as Louisiana and Arkansas adopted emancipation in their state constitutions. Emancipation was proceeding apace. Scant weeks after Lincoln and the Republicans won resounding victory in the November 1864 elections, the same Congress took its seats for its “lame duck” session. Lincoln pressed Congress to reconsider the measure in light of the election returns. “There is only a question of time as to when the proposed amendment will go to the States for their action,” Lincoln argued in his 1864 Annual Message on December 6, 1864. “And as it is to so go at all events, may we not agree that the sooner the better?” Congress agreed, passing the amendment by a vote of 119-56. The amendment then went to the states for ratification. Only time would tell whether the mechanism for keeping slavery out of the territories would suffice for uprooting it where it had long existed.