With Georgia's ratification on December 6 providing the necessary three-fourths majority of states, Secretary of State William Seward formally proclaimed the Thirteenth Amendment part of the Constitution on December 18, 1865. The amendment permanently abolished slavery and involuntary servitude except as punishment for crime, finishing the work begun by Lincoln's wartime Emancipation Proclamation, which had applied only to Confederate territory. Its ratification came eight months after Lincoln's assassination and Confederate surrender.
The Emancipation Proclamation of 1863 had been a war measure, freeing enslaved people only in Confederate-held territory and resting on the president's wartime powers rather than permanent constitutional authority. Abolishing slavery everywhere and for all time required amending the Constitution itself, a process Lincoln pushed hard for in his final year, famously the subject of intense congressional maneuvering dramatized in later films and histories.
Congress passed the amendment in January 1865, and state ratifications trickled in through the year, gaining urgency after Lincoln's assassination in April and the Confederacy's collapse. Southern states readmitted to the Union under Reconstruction were pressured, sometimes explicitly required, to ratify as a condition of restored representation. Georgia's ratification on December 6, 1865, pushed the tally past the necessary three-fourths threshold of 27 states.
Secretary of State William Seward, himself a survivor of an assassination attempt the same night Lincoln was shot, issued the formal proclamation on December 18, certifying the amendment's adoption. The brief text — 'Neither slavery nor involuntary servitude, except as a punishment for crime... shall exist within the United States' — ended over two centuries of legal slavery in America, though the nation's reckoning with its legacy, through Black Codes, Jim Crow, and ongoing civil rights struggles, had only just begun.