The Surprisingly Modern Origin of Paint by Numbers
Paint by numbers was invented in the 1950s not by an artist, but by a commercial illustrator trying to convince Americans that anyone could be a painter. It became an instant craze that sold millions of kits.
Dan Robbins created the kits while working for a Detroit paint company. He based the concept on Leonardo da Vinci, who reportedly taught his students by numbering canvases to simplify painting. While critics once mocked it as kitschy and low-brow, these kits are now highly collectable. They remain a massive phenomenon for people who want the creative satisfaction of art without needing formal training.
Source: Paint by number