In the entire world, there are only seven known “black books”—visually dramatic medieval illuminated manuscripts on vellum either stained or painted black. The existing examples date to the latter half of the 15th century. Additionally, all are a specific type of Christian volume known as a book of hours, an abbreviated collection of daily prayers or offices made for lay people.
New York’s Hispanic Society Museum & Library owns the oldest of these. Black Book of Hours, also called “Horae beatae marie secundum usum curie romane,” dates to circa 1458. It is one of the museum’s greatest treasures due to its rarity, but it is seldom displayed publicly. Indeed, it is very fragile and has been in need of conservation. In April 2025, it was announced that this small book, which is only about 5 3/4 by 4 inches, will be restored thanks to a prestigious double grant.
