Final answer:
The Confederate Army first launched an attack on the Union at Fort Sumter. The fort is situated in the city of Charleston, South Carolina. The significant assault marked the start of the American Civil War.
Step-by-step explanation:
The Confederate Army first attacked the Union at Fort Sumter, which is located in the city of Charleston, South Carolina. This attack marked the beginning of the American Civil War. The fort was strategically located in the harbor of Charleston, making it a vulnerable target for the Confederates and a significant loss for the Union side. Confederate forces launched a bombardment on Fort Sumter on April 12, 1861, and after two days, the Union soldiers there surrendered.
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