Crockett Johnson (October 20, 1906 – July 11, 1975) was the pen name of the American cartoonist and children's book illustrator David Johnson Leisk.
Born in New York City, Johnson grew up in Corona, Queens, New York, attended PS 16 and Newtown High School. He studied art at Cooper Union in 1924, and at New York University in 1925. He explained his choice of pseudonym as follows: "Crockett is my childhood nickname. My real name, Leisk was too hard to pronounce -- so -- I am now Crockett Johnson!"
Crockett Johnson was the writer and illustrator of over twenty books for children, including the beloved classic “Harold and the Purple Crayon,” six subsequent adventures starring Harold, and “The Carrot Seed,” written by his wife, Ruth Krauss. He was also the creator of the groundbreaking “Barnaby,” one of the most influential and ingenious comic strips of the twentieth century.
Johnson was not only a cartoonist and children’s book illustrator, but a painter whose particular interest was in picturing mathematical concepts. He created his series of more than 100 mathematical paintings inspired by geometric principles and mathematicians. He made an effort to differentiate his paintings from contemporary art in that his are based on the mathematics of geometry, not solely the shapes. In his 1971 article titled "Geometric Geometric Painting," published in Leonardo, Johnson describes this type of geometric painting as using shapes and lines to experiment with color and optic illusion for decoration, the evocation of emotion, representation of ancient symbols or other purposes unrelated to geometry.