The Emancipation Proclamation
After the Battle of Antietam, Lincoln issued the Emancipation Proclamation. The Emancipation of Proclamation freed all the slaves. This victory gave Lincoln the feeling that the war could be won. Even though this law was passed, the Southern states did not abolish slavery. The law only abolished slavery in the Union states. The Proclamation also allowed African Americans to fight on the Union's side. This boosted the Union's power, which in the end prevailed over the Confederacy.