1904: Theodor Seuss Geisel is born.

1925: At Dartmouth College, the humorous writer and poet penned the pseudonym “Seuss” after a drinking violation forbade him from writing for school publications. We can thank Prohibition for this one-of-a-kind byline.

1927: While studying at Oxford University, Seuss met and married his wife, Helen Palmer.

1937: After it was rejected 27 times, Seuss published his first children’s book, And to Think That I Saw It on Mulberry Street.

1940: Before the U.S. entered WWII, Seuss worked as a cartoonist, drawing over 400 editorial cartoons for the left-wing PM Magazine.

1943: Seuss joined the U.S. Army Air Forces as a captain and wrote Our Job in Japan, a military training film that became the basis for the 1947 Oscar-winning documentary feature, Design for Death.

1954: Horton Hears a Who! – featuring Horton the elephant for the second time and The Whos for the first – was published. Seuss was ever-vocal in his efforts to educate children, and many of his books were allegories for his own political and social concerns. The Lorax speaks to pollution, The Sneetches to racism, and Horton Hears a Who! to American anti-isolationism during WWII.

1957: A turning point came in Seuss’s career when he was asked to write a book in response to LIFE’s criticism of children’s poor reading levels. The result? The Cat in the Hat, which contains over 220 vocabulary words.

1966: How The Grinch Stole Christmas! was adapted into animated film.

1991: With 48 books in his repertoire and over 200 million copies sold, Seuss died at age 87. The New York Times called him the Modern Mother Goose.

Our Happy Birthday, Dr. Seuss: Kids’ Books, Art, & More Boutique opens Saturday, March 2, at 11AM ET.

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