On 31 Jan 1865, the U.S. Congress approved the 13th Amendment to the Constitution. This amendment abolishes slavery and involuntary servitude for the entire country. The wording was simple:
Neither slavery nor involuntary servitude, except as a punishment for crime whereof the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.
While President Lincoln’s Emancipation Proclamation freed slaves in the Confederate states, it did not apply to the entire country. To do that required federal law but merely enacting a statute, which could be rescinded or altered by Congress or a court, meant that the Constitution itself had to be amended. In April 1864 the amendment was passed in the U.S. Senate but faced difficulties in House of Representatives as many Democrats (due it being an election year) did not support it. And President Lincoln’s reelection did not look assured either. However with more Union military victories taking place and Lincoln soundly defeating General George McClellan in the November election, it emboldened Republicans to pass the amendment in the House in December 1864.
Lincoln got personally involved in the process by inviting individual representatives to meet with him. And he put pressure on representatives from border-states to change their votes to pass it. He authorized his supporters in the House to offer plum positions and other inducements to get their vote (a time-honored tradition in Washington politics). He left it up to his allies on how to do it. Some drama ensued when word of a Confederate peace commission having been dispatched to Washington, but it turned out to be false. And the vote for the amendment took place on 31 January 1865. It passed by 119-56 receiving the required two-thirds required by the Constitution. Then with a joint resolution of Congress the following day, the 13th Amendment was sent to the state legislatures for ratification.
Ratification
The ratification process began immediately but sadly President Lincoln, who was assassinated on 14 April 1865, did not see it ratified in December. Here is a list of the states that ratified, which does include former Confederate states who ratified after rejoining the Union.
1 Illinois Feb 1, 1865
2 Rhode Island Feb 2, 1865
3 Michigan Feb 3, 1865
4 Maryland Feb 3, 1865
5 New York Feb 3, 1865
6 Pennsylvania Feb 3, 1865
7 West Virginia Feb 3, 1865
8 Missouri Feb 6, 1865
9 Maine Feb 7, 1865
10 Kansas Feb 7, 1865
11 Massachusetts Feb 7, 1865
12 Virginia Feb 9, 1865
13 Ohio Feb 10, 1865
14 Indiana Feb 13, 1865
15 Nevada Feb 16, 1865
16 Louisiana Feb 17, 1865
17 Minnesota Feb 23, 1865
18 Wisconsin Feb 24, 1865
19 Vermont Mar 8, 1865
20 Tennessee Apr 7, 1865
21 Arkansas Apr 14, 1865
22 Connecticut May 4, 1865
23 New Hampshire Jul 1, 1865
24 South Carolina Nov 13, 1865
25 Alabama Dec 2, 1865
26 North Carolina Dec 4, 1865
27 Georgia Dec 6, 1865 *
28 Oregon Dec 8, 1865
29 California Dec 19, 1865
30 Florida Dec 28, 1865
31 Iowa Jan 15, 1866
32 New Jersey Jan 23, 1866
33 Texas Feb 18, 1870
34 Delaware Feb 12, 1901
35 Kentucky Mar 18, 1976
36 Mississippi Mar 16, 1995 *
The amendment was ratified in 309 days with Georgia giving it the required number of votes to formally amend the Constitution. Delaware, Kentucky, New Jersey and Mississippi initially rejected it (but approved it later). However, Mississippi did approve it on 16 Mar 1995 but failed to notify the U.S. Archivist. It became official in 2012.
Sources:
Britannica.com: Thirteenth Amendment
History.com: 13th Amendment
Constitution Annotated: Thirteenth Amendment
Ratification of Constitutional Amendments