On Feb. 1, 1865, Illinois became the first state to ratify the 13th Amendment of the Constitution, which officially ended slavery and involuntary servitude. Ratifying the 13th Amendment was one of President Lincoln’s top priorities.

Lyman Trumbull, a U.S. senator from Alton, co-authored the amendment that passed Congress and was sent to the states for ratification on Jan. 31, 1865.

In order to propose a constitutional amendment, both the U.S. House and the Senate have to approve a resolution to amend the Constitution by a two-thirds majority. The proposal then goes to the state legislatures to ratify. In order for an amendment to become law, three-fourths of the state legislatures must approve it.

On Dec. 6, 1865, Georgia became the 27^th state to ratify the amendment, securing the three-fourths majority needed to add the amendment to the Constitution.