There were, of course, many major battles that were important to the outcome of the American Civil War. Let us look at three of these.
First, there was the Battle of Antietam. This battle was fought on September 17, 1862 near the town of Sharpsburg, Maryland. It was the bloodiest one-day battle in American history. This battle was inconclusive, but it was important for two reasons. First, it stopped a Confederate invasion of the North. Second, and perhaps more importantly, it allowed President Lincoln to issue the Emancipation Proclamation. He had wanted to issue this, but was waiting for something that could be seen as a military victory. He did not want people to think he was issuing the Proclamation out of desperation. With the “win” at Antietam, he issued the Proclamation and changed the face of the war.
Second, there was the Battle of Vicksburg, which ended in July of 1863. Vicksburg was the last city on the Mississippi River that remained in Confederate hands. It prevented the Union from having complete control of the river. When it fell, the Union controlled the river and could cut the western half of the CSA off from the eastern half.
Finally, there was the Battle of Atlanta. This battle was fought in August of 1864. When the US won, it did three things. First, it ensured that Lincoln would win reelection and that there would be no peace treaty with the South. Second, it cut the South in half again, allowing the North to prevent supplies from the Deep South from coming to help the army farther north. Finally, it allowed Sherman’s “March to the Sea,” which devastated the South and weakened its ability and will to fight.
These are some of the more important battles of the war.