Suppose The American Civil War, also known as the War Between the States, was a conflict fought in the United States from 1861 to 1865. It was primarily the result of the long-standing controversy over the enslavement of black people. The war broke out with the election of Abraham Lincoln, who opposed the expansion of slavery into the western territories, and the Southern states seceded from the Union.
Can we infer that "All states in the Union supported slavery during the Civil War."? Yes, no, or maybe?