Answer:
My Understanding: sorry if this does not match what you asked :)
Step-by-step explanation:
The Emancipation Proclamation was a statement by Abraham Lincoln on January 1st, 1863. He used this proclamation to free any slaved person in the confederate states at that moment and from thereon.
The goals of the war were solely on the idea of all slaves being free in the southern states, and for the north to be peaceful and unionized with the south, since the south wanted to be independent and to keep the idea of slavery and slaves. The goals were not really changed all too much, but rather enforced the idea of the northern states.