The U.S. president who issued the Emancipation Proclamation during the Civil War was Abraham Lincoln. Signed on January 1, 1863, the proclamation declared that all enslaved people in the Confederate states were to be set free. While it did not immediately free any enslaved individuals, it was a significant step in the fight against slavery and shifted the war's focus towards liberation. The proclamation also allowed for the enlistment of African American soldiers in the Union Army, bolstering its numbers and highlighting the moral imperative of the Union's cause. Lincoln's leadership in this area was crucial for shaping future policies.