Claus Leggewie in The LA Review of Books:
ON OCTOBER 16, 1937, a certain Grete de Francesco of Milan sent a 12-page, handwritten letter to the “esteemed Mr. Thomas Mann,” along with a copy of her recently published book Die Macht des Charlatans (The Power of the Charlatan). Though unknown to the world-famous author, de Francesco insisted that Mann was the “intellectual patron saint” behind her own work: “This book would never have been written,” she explained, “were it not for the wake-up call” provided in 1930 by his novella Mario and the Magician.
As his various underlinings show, Mann read the letter carefully, and he even complied with de Francesco’s request to recommend her study for review in a prominent journal. The book turned out to be even more successful in the United States when it was released by Yale University Press in 1939 (in a translation by Miriam Beard), and it eventually became well known among exiled writers and also in Hitler’s Germany, where officials recognized its explosive potential and promptly pulped as many copies as they could get hold of. Since then, de Francesco’s study was largely forgotten — until a brilliantly annotated reprint appeared from German publisher Die Andere Bibliothek in 2021.
More here.