Karl Friedrich May (1842 – 1912) was a German writer best known for his adventure novels set in the American Old West. His main protagonists are Winnetou and Old Shatterhand. He is one of the best-selling German writers of all time with about 200 million copies worldwide.

Adolf Hitler was an admirer, who noted in Mein Kampf that the novels 'overwhelmed' him as a boy, going as far as to ensure 'a noticeable decline' in his school grades. Hitler defended May against critics in the men's hostel where he lived in Vienna, as the evidence of May's earlier time in jail had come to light; although it was true that May had never visited the sites of his American adventure stories, this made him a greater writer in Hitler's view since it showed the author's powers of imagination.

Hitler later recommended the books to his generals and had special editions distributed to soldiers at the front, praising Winnetou as an example of 'tactical finesse and circumspection'.

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