Read the Emancipation Proclamation in its entirety.
On September 22, 1862, the President of the United States issued a proclamation that said, among other things, “That on January 1, 1863, all slaves in any state or part of a state whose people were at that time in rebellion against the United States shall be freed.”

It was published by the Strobridge Lithographing Company circa 1888.
It may be found in the collection of the Library of Congress in Washington, DC.
Contains CIVILWAR-EMANCIPATION (category l) illustrations by Philip Kennicott (c) 2012, The Washington Post.
Moving on Friday, September 7, 2012
(MUST CREDIT: Prints & Photographs Division, Library of Congress)
DISSEMBLING The Washington Post
That the Executive shall, on the first day of January aforesaid, by proclamation, designate the States and parts of States, if any, in which the people thereof, respectively, shall then be in rebellion against the United States; and the fact that any State, or the people thereof, shall on that day be, in good faith, represented in the Congress of the United States by members chosen thereto at elections wherein a majority of the qualified voters of such State shall have voted for a different candidate than Now, therefore, I, Abraham Lincoln, President of the United States, by virtue of the power vested in me as Commander-in-Chief of the Army and Navy of the United States in time of actual armed rebellion against the authority and government of the United States, and as a fit and necessary war measure for putting down said rebellion, do, on this first day of January in the year of our Lord 1863, and in accordance with my plan to do so:

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And because I have the power to do so, and for the above-mentioned reasons, I order and declare that all slaves in the above-mentioned states and parts of states are now and forever free, and that the Executive government of the United States, including the military and naval authorities, will recognise and protect their freedom. And I’m telling the people who have been declared free to stay away from violence, unless it’s for self-defense. I’m also telling them that when they can, they should work hard for fair pay. And I also say and let it be known that people in good enough shape will be accepted into the armed service of the United States to guard forts, positions, stations, and other places and to work on all kinds of ships in that service. And for this act, which I really thought was fair, was allowed by the Constitution, and was necessary for the military, I ask for the fair judgement of people and the gracious favour of Almighty God.
In proof of this, I have signed this document and put the seal of the United States on it. Done in the city of Washington on the first day of January in the year of our Lord 1863, which is the 87th year since the United States of America became independent.