History 101: On September 22, 1862, following the Union “victory” at the Battle of Antietam, the Preliminary Emancipation Proclamation was issued
Today is the 150th Anniversary of the Emancipation Proclamation
Although January 1st, 1863, is the date most Americans identify as the day the Emancipation Proclamation officially took effect, the ideals of the Proclamation had been carefully contemplated by President Lincoln many months before.
Lincoln first proposed the idea of the Emancipation Proclamation to his cabinet in the summer of 1862 as a war measure to cripple the Confederacy. Lincoln surmised that if the slaves in the Southern states were freed, then the Confederacy could no longer use them as laborers to support the army in the field, thus hindering the effectiveness of the Confederate war effort. As an astute politician, however, Lincoln needed to prove that the Union government could enforce the Proclamation and protect the freed slaves. On September 22, 1862, following the Union “victory” at the Battle of Antietam, the Preliminary Emancipation Proclamation was issued, this preliminary proclamation would go into effect three months later on January 1, 1863.
The Emancipation had an immediate and profound effect on the course of the war. In addition to saving the Union, freeing the slaves now became an official war aim, garnering passionate reactions from both the North and the South. The Proclamation also allowed for African-Americans to join the Union’s armed forces, and by the end of the war nearly 200,000 would honorably serve.
Initially the Proclamation applied just to the states in rebellion, but it paved the way for the 13th Amendment, adopted on December 6, 1865, which officially abolished slavery in the United States.
https://www.civilwar.org/150th-anniversary/emancipation-proclamation-150.html#
