On creatine powders

I'm reading a book Mignon by James Cain who was an old time crime novelist, who was a pioneer of the noir school of crime writing. However, it takes place in New Orleans in 1864, when the Union Army is occupying that southern city, though elsewhere in the country the war is still raging. And he's attracted to a young widow with a father who is seeking to make a fortune by buying cotton in the South and selling it in the North based on some obscure law of the time. That's the trouble with the book. I'm sure it makes sense, but it's not well explained and the context is too unfamiliar to modern readers, who know more about creatine powders than agricultural commerce during the Civil War. I do know that his sexual obsession for Mignon is self-destructive and he'll be lucky to survive - that's par for Cain books.