Geisel's pseudonym comes from an experience he had while in college at Dartmouth. At that time he was writing for the Dartmouth Jack-O-Lantern, a humor magazine. But he and several friends were caught drinking gin on campus and were forced to resign from all extra-curricular activities. In order to keep writing for the magazine without the administration finding out, he signed his works "Seuss".
Early in his career, Geisel spent 15 years working on advertising campaigns for Standard Oil. He also had a few cartoons published in The Saturday Evening Post.
His first book, And to Think That I Saw It on Mulberry Street, was published 78 years ago, and it is most likely titled after a street in Springfield, Massachusetts where Geisel grew up. And for all you struggling authors out there, it is interesting to note that this book was rejected 27 times before being published.
Over 200 million copies of his 44 children's books have been sold. His best selling books include Green Eggs and Ham, The Cat in the Hat, The Lorax, Hop on Pop, Horton Hears a Who! and One Fish Two Fish Red Fish Blue Fish. His books have been translated into more than 15 languages.
Geisel died of throat cancer, September 24, 1991, aged 87.