The Bute Book of Hours, a prayer book that may have belonged to Henry VIII, is up for auction at Sotheby's.
The lot will cross the block in a Medieval and Renaissance Manuscripts auction in London on December 6.
It's named for the Fifth Marquess of Bute, who acquired it in an auction in 1918, but dates back to the 1500s.
The evidence linking the book to Henry hinges on its illustrations, reports the Guardian newspaper.
They show a man wearing a great chain of office, indicating he is of royal blood. There are also references to plague, which is known to have struck London during 1499-1500.
Henry would have been around eight years old at the time.
Other illustrations show Henry VIII's great uncle, Henry VI, in the role of a saint.
While he was never canonised by the Catholic Church, Henry VI was considered a religious figure by his family - who attributed a number of miracles to him.
These included the cure of a girl afflicted with scrofula (a virulent skin disease) and the revival of a plague victim. They also considered him a martyr following his death at the hands of Richard III in the War of the Roses.
Somewhat ironically, the book features one of the few surviving portraits of former Archbishop of Canterbury Thomas Beckett (1119-1170), a cult figure in English Catholicism.
Henry VIII ordered Beckett's bones to be destroyed and all images of him destroyed when he dissolved the monasteries in 1538.
The book last sold for £154,000 ($192,137)) in 1983. It's expected to make £1.5m-2.5m ($1.8m-3m) this time around.
We're selling this truly remarkable document signed by Henry VIII.
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