The American President who issued the Emancipation Proclamation was Abraham Lincoln. Signed on January 1, 1863, during the Civil War, this executive order declared the freedom of all enslaved people in Confederate-held territory. Lincoln believed that emancipation would weaken the Confederacy and shift the war's focus towards the moral imperative of ending slavery. The Proclamation did not immediately free all enslaved individuals; however, it laid the groundwork for the eventual abolition of slavery through the passage of the 13th Amendment in 1865. Lincoln's actions significantly impacted America's social and political landscape.