Final answer:
The significant early battle of the Civil War that occurred in April of 1861 was the Battle of Fort Sumter.
Step-by-step explanation:
The significant early battle of the Civil War that occurred in April of 1861 was the Battle of Fort Sumter. It was the first engagement of the war and took place in Charleston, South Carolina. The Confederate forces, under General P.G.T. Beauregard, bombarded the Union-held Fort Sumter, resulting in the eventual surrender of the Union troops.
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