Final answer:
Jefferson Davis led the Confederate States during the American Civil War.
Step-by-step explanation:
During the American Civil War, the Confederate States were led by Jefferson Davis. Davis served as the President of the Confederate States of America from 1861 to 1865. Abraham Lincoln, on the other hand, was the President of the United States during this time, leading the Union. It's important to note that Bismarck was the Chancellor of the German Empire and Cavour was a statesman in the Kingdom of Sardinia, unrelated to the American Civil War.
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