What document declared the freedom of slaves in areas not controlled by the Union?

The Emancipation Proclamation is the document that declared the freedom of slaves in areas not controlled by the Union. Issued by President Abraham Lincoln on January 1, 1863, during the Civil War, it was a strategic move intended to weaken the Confederacy by liberating their enslaved workforce. Importantly, the proclamation applied only to the Confederate-held territories, meaning that it did not immediately free all enslaved people in the United States but marked a significant step towards the abolition of slavery. This executive order also allowed for the enlistment of African American soldiers in the Union Army, adding strength to the Union's efforts.

The other options do not fulfill the same purpose. The Gettysburg Address, while a powerful speech that emphasized equality and the dedication to the soldiers who fought, did not declare emancipation. The Declaration of Independence laid the groundwork for American ideals concerning liberty and rights but predated the Civil War and did not specifically address slavery. The Thirteenth Amendment, ratified later in 1865, formally abolished slavery throughout the entire United States, but it came after the Emancipation Proclamation and was part of the legislative process to ensure permanent freedom for all enslaved individuals.