Filling in the Blanks: A Prehistory of the Adult Coloring Craze

Now in its third year, the campaign sees, on the first week of February, archives, special collections, and libraries take to social media with individual images and even entire books compiled from their holdings for the public to color. While publishers may have informally expected these monochrome images to be colored by some readers, it wasn’t until the eighteenth century that the practice was formalised in the first purpose-made coloring books. Robert Sayer’s The Florist, published in London in 1760, was one of the first books where the author explicitly intended readers to color in the images.

Source: publicdomainreview.org