The first reading of the Emancipation Proclamation before President Abraham Lincoln's Cabinet, painted by F.B. Carpenter. (Library of Congress) (Library of Congress Prints and Photographs Division/Library of Congress Prints and Photographs Division)

On New Year’s morning of 1863, President Abraham Lincoln hosted a three-hour reception in the White House. That afternoon, Lincoln slipped into his office and — without fanfare — signed a document that changed America forever.

It was the Emancipation Proclamation, decreeing “that all persons held as slaves” within the rebellious Southern states “are, and henceforward shall be, free.”

However, the proclamation did not immediately free any of the nation’s nearly 4 million slaves. The biggest impact was that for the first time, ending slavery became a goal of the Union in the bloody civil war with the Confederacy.

The news sent shock waves throughout the divided country. Southern newspapers responded with outrage. Lincoln’s action was “the most startling political crime, the most stupid political blunder yet known in American history,” the Richmond Enquirer thundered. “The Southern people have now only to choose between victory and death.”

In the North, the Cleveland Morning Leader exulted “The day of Jubilee has arrived, and the all important words ‘Be Free’ have been spoken.” The New York Times declared “President Lincoln’s proclamation marks an era in history, not only of this war, but of the world.” But some Northern whites opposed fighting for the freedom of black slaves. The Cincinnati Enquirer said Lincoln’s proclamation represented the “complete overthrow of the Constitution he swore to protect and defend.”

Free African Americans in the North celebrated the news. “We are all liberated by this proclamation,” said the noted orator and former slave Frederick Douglass. “Everybody is liberated. The white man is liberated, the black man is liberated, the brave men now fighting the battles of their country against rebels and traitors are now liberated.” But Douglass cautioned that the proclamation was only a first step; slaves who celebrated the proclamation risked being beaten or hung.

The proclamation was not a surprise. Lincoln had presented his draft of a preliminary order at a Cabinet meeting on July 22, 1862. Secretary of State William Seward suggested the president wait until after the North had scored a fresh win over Southern troops before releasing the document. On Sept. 22, a few days after Union forces claimed victory in the Battle of Antietam, Lincoln issued the preliminary proclamation. It stated that if Southern states did not surrender by Jan. 1, 1863, the president would issue a final order to make their slaves “forever free.”

The fighting continued. Some doubted Lincoln would back up his threat. But on the afternoon of Jan. 1, he paused only to steady his hand before signing the final Emancipation Proclamation. “I never, in my life, felt more certain that I was doing right than I do in signing this paper,” Lincoln said. “If my name goes into history, it will be for this act, and my whole soul is in it.”

Many abolitionists criticized Lincoln’s action as too limited. The proclamation purported to free millions of slaves in the Southern states that had seceded from the Union. It exempted 850,000 slaves in border states and parts of three Southern states that were not in rebellion. The New York Herald said of Lincoln’s order: “While the proclamation leaves slavery untouched where his decree can be enforced, he emancipates slaves where his decree cannot be enforced.”

While Lincoln believed freeing the slaves was the right thing to do, his proclamation was a strategic “war measure” in the battle to defeat the Confederacy. The proclamation allowed black men to join the Union military forces. Eventually, nearly 200,000 African Americans fought for the North. By making the abolition of slavery a Union goal, the proclamation also discouraged intervention by anti-slavery foreign nations, such as England, on the Confederate side.

Lincoln, who won reelection in 1864, knew his war order was temporary and pressed Congress to amend the Constitution to end slavery forever. By Jan. 31, 1865, both houses of Congress passed the 13th Amendment that “neither slavery or involuntary servitude … shall exist in the United States.”

Slavery officially ended on Dec. 18, 1865 after 27, or two-thirds, of the 36 states ratified the amendment. Lincoln did not live to see the culmination of his proclamation. On April 14, 1865 — five days after the South surrendered — the president was shot and killed by Southern sympathizer John Wilkes Booth at Ford’s Theatre in Washington.

The end of slavery was just the beginning of a long struggle by African Americans for full rights as U.S. citizens. Racial segregation in the South continued into the 1960s in everything from public accommodations to schools. At the dedication of the Lincoln Memorial in Washington, D.C., in 1922, the crowd of 50,000 people was segregated by race.

An integrated crowd of more than 250,000 swarmed around the Lincoln Memorial in August 1963 for the March on Washington. The Rev. Martin Luther King Jr. began his “I Have A Dream” speech by praising the Emancipation Proclamation as a “great beacon light of hope to millions of Negro slaves who had been seared in the flames of withering injustice. … But 100 years later, the Negro still is not free.”

Though the outcome was far from certain when Lincoln signed the proclamation, one group of black Americans had faith when they met in mid-January 1863 at the Oak Grove school in Leesburg, Ohio. The group agreed on a resolution expressing hope that the proclamation would lead to freedom for all black people in America.

“Should all this be accomplished,” the resolution said, “the name of Abraham Lincoln will ever be gratefully remembered by the colored race of America; and the 1st of January should be celebrated to our latest posterity as the most important event in all our history.”

Ronald G. Shafer is a freelance writer in Williamsburg, Va., and a former Washington political features editor at the Wall Street Journal.

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