South Dakota was not a Confederate State. The state of South Dakota was created in 1889, after the American Civil War, and was never part of the Confederate States of America. The Confederate States of America was formed in 1861 by eleven southern states that seceded from the United States. South Dakota is located in the northern part of the country and was not one of the states that seceded. The Civil War lasted from 1861-1865 and resulted in the victory of the Union (Northern) states and the abolition of slavery in the United States.