(NEXSTAR) – People go nuts for doughnuts, especially on National Doughnut Day.

First celebrated in 1938, National Doughnut Day was organized by the Salvation Army to celebrate the volunteers who traveled overseas during WWI to provide support for the troops, sometimes by frying up doughnuts on the front lines. These “Donut Lassies,” as they came to be known, helped to popularize the treat among returning GIs, according to the Salvation Army.

Today, National Doughnut Day is celebrated every year on the first Friday in June (and also, somewhat strangely, in early November). Despite all the empty calories, there’s a whole lot to celebrate too: The doughnut has had a long, interesting history in the United States.

Curious to know why doughnut boxes in movies are always pink? Or how they came to be associated with police? Here’s a dozen things you might not have known about one of America’s favorite treats.

• Matt Groening, the creator of “The Simpsons,” once revealed to Entertainment Weekly that Homer’s snack of choice was a doughnut because Groening’s own father, who was also named Homer, was a big fan. “Homer originated with my goal to both amuse my real father, Homer, and just annoy him a little bit,” Groening said in the 2010 interview. Groening admitted that Homer Simpson shared no other attributes with his real father, who was an “athletic, creative, intelligent filmmaker.”

• There’s a reason we associate police officers with doughnuts, and it’s not as silly as comedians would have you believe. Cops working the graveyard shift in the middle of the 20th century had few options for late-night or early-morning meals, but most doughnut shops and bakeries would start making their goods before the sun came up. “They could pack lunch, pray for an all-night diner on their beat, or fill up on doughnuts,” said Norm Stamper, the former chief of the Seattle Police Department, as quoted in “The Donut: History, Recipes and Lore from Boston to Berlin” by Michael Krondl. “Doughnuts usually won out,” he said.

• Speaking of cops and doughnuts: In 2013, amid the aftermath of the Boston Marathon Bombing, the Boston Police Department specifically requested that several Dunkin’ locations remain open despite an area-wide lockdown, specifically so they could feed officials who were out hunting the second suspect. “At the direction of authorities, select Dunkin’ Donuts restaurants in the Boston area are open to take care of needs of law enforcement and first responders,” a spokesperson for the chain said at the time, as reported by Boston.com. Those locations provided coffee and food to police and first responders free of charge.

• Doughnut boxes are often depicted as being pink in television or movies because pink doughnut boxes are common in Southern California, where most of those shows or films are made. “Any time you see a movie or sitcom set in New York and a pink doughnut box appears, you know [filming] obviously took place in L.A.,” one of the box manufacturers told the Los Angeles Times in 2017.

• Another thing about pink doughnut boxes: Those boxes likely became ubiquitous in Southern California thanks to Cambodian refugee Ted Ngoy and his protegee Ning Yen, according to the L.A. Times. Stories differ, but relatives and local businesspeople agree that either Ngoy or Yen (or both) asked their supplier for a more affordable alternative to the then-standard white boxes. Pink was cheaper, and it soon became the color of choice for other Cambodian immigrants who opened their own doughnut shops in Southern California. (Yen’s son offered a different explanation to the L.A. Times, claiming that his father originally wanted red boxes — red being a symbol of good fortune — but “the mills kept sending it back pink.”)

• Elvis Presley only did one commercial during his career, singing the jingle for Southern Maid Donuts in 1954. “You can get them piping hot after 4 P.M., you can get them piping hot,” he sang. “Southern Maid Donuts hits the spot, you can get them piping hot after 4 P.M.” According to the company, Presley became a fan of Southern Maid Donuts while appearing at the Louisiana Hayride Show in Shreveport, and even “frequented” the local shop while he was there.

• Despite persisting rumors to the contrary, President Kennedy did not tell the crowds in West Berlin that he was a “doughnut” during his famous “Ich bin ein Berliner” speech in 1963. It’s true that “Berliner” can be interpreted as “jelly doughnut” in certain contexts (mostly outside of Berlin), but Kennedy was correct in his usage of the term in conveying that he was a resident of Berlin in spirit, The Atlantic reported. The speech was also reviewed beforehand for accuracy by Robert Lochner, a Berlin-born chief German interpreter for the United States, as well as the mayor of Berlin, according to Snopes.

• Krispy Kreme’s history dates back to 1933, but it wasn’t until 1937 that its shops began selling doughnuts directly to customers. As the story goes, Krispy Kreme founder Vernon Rudolph was selling his doughnuts wholesale to grocery stores during the first few years, but the demand from passersby outside of his North Carolina shop convinced him to cut a hole in the wall and begin selling to customers on the sidewalk.

• The doughnut hole treats at Dunkin’ and Krispy Kreme, the two leading doughnut chains in the U.S., are not produced by traditional methods (i.e., by punching a hole from the center of uncooked dough, and then frying the resulting “rings” and the “holes” separately). Both chains currently make their doughnuts by pressing out the dough in rings — and not circles — meaning there’s no need to punch any “holes” in the dough, and therefore no excess “hole” portion to use for the specific purposes of making Munchkins or doughnut holes.

• There are more doughnut shops in Canada, per capita, than any other nation on the planet — and the residents of Canada eat more doughnuts than anyone else, the Canadian Broadcasting Corporation once reported. It’s likely this statistic remains accurate today. Canada’s largest restaurant chain is the Tim Hortons coffee-and-doughnut shop, which, by its own account, is visited by 80% of Canadians “at least once a month.”

• Our neighbors to the north may consume the most doughnuts per capita, but America is no slouch, either — especially in the Northeast. A recent study conducted by BestPlaces.net determined that the Providence-Warwick metro area in Rhode Island had the most doughnut shops per capita of anywhere in the country, followed by metro areas in Massachusetts, Connecticut, Pennsylvania and New York. In fact, only one major region from outside the Northeast cracked the study’s “Top Ten Donut Cities” list: the Dallas-Fort Worth-Arlington metro area, which came in at No. 9.

• The Salvation Army still celebrates National Doughnut Day. Past events have included fundraisers, special deliveries to veterans, doughnut drop-offs to first responders and frontline workers, and other charitable nationwide events. For those who want to participate, the Salvation Army suggests frying up a batch using the original “Donut Lassies” recipe and then sharing the sweets with “whomever needs them most.”