0h 38min, sep 17, 1862 y - Battle of Antietam
Description:
Antietam was the bloodiest day of in American history. This was in Sharpsburg, MD, a border state, so Union victory ended the Confederate effort to get Maryland to secede. Additionally, Lincoln issued his Emancipation Proclamation after this.
Added to timeline:
Date:
0h 38min, sep 17, 1862 y
Now
~ 163 years ago