Complex sentence: After the start of the American Civil War, he returned to his native Georgia and became active in banking and supporting the war effort in several ways including founding the Importing and Exporting Company of Georgia one of the blockade runners of the American Civil War.
Split into simpler sentences: After the start of the war, he returned to his native Georgia and became active in banking and supporting the war effort in several ways. H founded the Importing and Exporting Company of Georgia, which operated blockade runners of the American Civil War.