The <span>Emancipation Proclamation ended slavery and set all slaves free.
It was signed on September 22nd, which was soon after the Union's victory against the Confederates in the Battle of </span><span>Antietam.
It was this victory that prompted President Lincoln to pass the </span>Emancipation Proclamation.
So the answer is A. S<span>eeing the Union’s effectiveness at the Battle of Antietam.</span>
What’s the question to this ? And what excerpt to read ?
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