This posting is somewhat dated, alas, but here goes.
Last fall, Stay Thirsty Press launched a "free promotional" weekend on Amazon -- a practice that is not at all uncommon these days. The idea is that as more people read a work, they will tend to pass along the good word. With any luck, these "promotionals" lead to sales in the future.
Under the category of "Music/Biographies" (which, we must assume, includes historical fiction as well), Charlie Brown's book on Wiz Khalifa finished #3, and Andrew Morris' volume on Justin Bieber took the #2 slot. Topping the list was Paganini's Fire.
How often does a 19th century violinist top finish ahead of two pop stars? Let us hope that this novel is finally beginning to gain some recognition!