Final answer:
The decisive battle of the war was fought at Gettysburg during the American Civil War in 1863.
Step-by-step explanation:
The decisive battle of the war was fought at Gettysburg. It took place during the American Civil War from July 1 to 3, 1863. The battle was fought between the Confederate Army of Northern Virginia, led by General Robert E. Lee, and the Union Army of the Potomac, commanded by General George G. Meade.
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