For what reasons did Southern states begin to secede in 1861, and what events led to the breakout of the Civil War? You should write a minimum of three paragraphs to earn a passing grade, and each paragraph should be at least 6 sentences long. I need 5 paragraphs. Why was the Battle of Gettysburg a decisive turning point in the Civil War? Write a minimum of three paragraphs to earn a passing grade, and each paragraph should consist of a minimum of 6 sentences. The minimum is write 5 paragraphs.