17h 37min, may 30, 1854 y - Kansas Nebraska Act
Description:
 The Kansas-Nebraska Act was passed by the U.S. Congress on May 30, 1854. It allowed people in the territories of Kansas and Nebraska to decide for themselves whether or not to allow slavery within their borders. 
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Date:
17h 37min, may 30, 1854 y
Now
 ~ 171 years ago