That hat on Bartholomew Cubbins's head certainly seems familiar, doesn't it…? Of course! It's a red version of the feathered cap worn by Robin Hood, Peter Pan, Green Arrow, and other Lincoln green clad heroes. Because of this, many people call it a Robin Hood or Peter Pan hat, but its actual name is the archer's hat—a favorite accessory of trick-or-treaters and ren faire enthusiasts since time immemorial.

But here's where things get all brain snacky. Archers didn't wear archer's hats because they are weaksauce protection on medieval battlefields. Instead, archers would wear a sallet, or any number of other metal helms into battle—depending on the era or country. Actually, Robin Hood, assuming he even existed at all, probably didn't wear an archer's hat either. He most likely would have gone with a hood, cowl, or maybe a chaperon. Then again, maybe he wasn't a hat guy.

So where did the archer's hat of Hood, Pan, and Cubbins fame come from? Chances are, it's the same place America gets most of its cultural imagery: the movies. Old Hollywood films, particularly those featuring such swashbucklers as Errol Flynn, are the most likely candidates for the invention of the archer's hat. A noteworthy sample is, of course, Flynn's 1938 film The Adventures of Robin Hood. Also, Peter Pan wasn't featured wearing a hat until the 1924 silent film and later Disney's 1953 rendition. In J.M. Barrie's Peter Pan and Wendy, Peter is hatlessly "clad in skeleton leaves and the juices that ooze out of trees." (Source).

But that doesn't mean Hollywood necessarily plucked this famously feathered cap out of air, thin or thick. The Phrygian could have served as inspiration for the archer's hat. Sometimes called the "liberty cap," the Phrygian was historically worn by emancipated Roman slaves to show their freedom and by revolutionaries during the French Revolution. The connection between the two is further illustrated by 19th-century drawings depicting Robin Hood wearing a Phrygian cap with an archer's feather stuck in it (such as this one by Howard Pyle). And let's not forget the association both Robin Hood and Peter Pan have with the ideals of freedom and liberty.

Oh, and did we mention that The 500 Hats of Bartholomew Cubbins came out in 1938—the same year as Flynn's famous Robin Hood film? Coincidence? Yeah, probably. But it's a fun one nonetheless.
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You might have noticed that The 500 Hats of Bartholomew Cubbins contains a rather unusual dedication. The book is dedicated to a Chrysanthemum-Pearl (aged 89 months, going on 90). That makes her… (doing some math)… 7 years and 5 months going on 7 years and 6 months. So a little girl. But what little girl was so special that Dr. Seuss would dedicate a whole book to her and count her life by months lived?

No one. And we mean that literally. Chrysanthemum-Pearl was Dr. Seuss's pretend daughter, a figment of his obviously super-active imagination. Since his first wife, Helen, and he could not have children, Seuss simply created one. He would brag about her accomplishments, include her name in Christmas cards, and, yes, even dedicate entire books to the seven-year-and-five-month-old phantasm. (Source: Dr. Seuss: American Icon by Philip Nel)

Want to have great ideas like Dr. Seuss? Then we suggest you get on the move and don't stop. See, Dr. Seuss got the ideas for his first two books when he was traveling somewhere. The first book, And to Think That I Saw It on Mulberry Street, came to him while on the Kungsholm. As the boat cut through the water, Seuss began to listen to the rhythm of the engines and received the idea of the book.

Next, while riding on a train from Springfield to New York, Seuss noticed the man sitting in front of him was wearing a hat. He "'decided [the man] was so stuffy that he'd probably grow another [hat]'" should Seuss reach up and pluck it off his head. And, voilà, book number two was born. Moral of these stories: keep on the move, keep seeing new things, and keep having new ideas. (Source: Dr. Seuss and Mr. Geisel: A Biography by Judith Morgan and Neil A. Morgan)

Dr. Seuss was a Random House guy his whole life. It seems they treated him well, and we know he did good by them. But Seuss's first two books, Mulberry Street and 500 Hats, were both published by Vanguard Press before Seuss hopped over to Random House, meaning that for years, these two members of the Seuss family were kind of like orphans.

Then, in 1987, Random House decided they needed the complete Seuss canon to celebrate Mulberry Street's 50th anniversary. They began negotiations. About a year later, they said screw negotiations and just bought Vanguard Press—like all of it. And Dr. Seuss was pretty stoked. Now his entire library had found a home, and he could finally make some changes to his first two novels—like removing the "funeral black" cover from 500 Hats. (Source: Dr. Seuss and Mr. Geisel: A Biography by Judith Morgan and Neil A. Morgan)