A brutal murder, a nefarious plot, a coded letter. After five hundred years, the most notorious mystery of the Renaissance is finally solved. The attempted assassination of the Medici brothers in the Duomo in Florence in 1478 is one of the best-known examples of the machinations endemic to the age.

More than five hundred years later, Marcello Simonetta, working in a private archive in Italy, stumbled upon a coded letter written by Federico da Montefeltro, the Duke of Urbino, to Pope Sixtus IV. Using a codebook written by his own ancestor to crack its secrets, Simonetta unearthed proof of an all-out power grab by the Pope for control of Florence.

In The Montefeltro Conspiracy, Simonetta unravels this plot in detail. View photographs and more images of the coded letter at doubleday.com/montefeltro.

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Watch Steven Pressfield discuss Killing Rommel at length at KillingRommel.com.

Read a review of Killing Rommel at GalleyCat and an excerpt at Military.com.

Praise for three-time New York Times bestselling author Leigh Montville’s latest book The Mysterious Montague:

“an entertaining read for the golf lit completist…” —Publishers Weekly

Leigh Montville “…hits the pin in one with this page-turning account of a long-forgotten golfer…Explaining why reporters loved to write about Montague, the author declares, ‘Intrigue is a better seller than great golf any day.’ Here, he gives readers both.” —Kirkus, starred review.