Holidays have always been one of the aspects of a society that helps to bind it together, giving various people an opportunity to come together in a shared celebration. While there are many holidays in the real world, there are also several that appear in various fictional contexts.

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Various television series, both comedies and dramas, have done a great deal to flesh out their universes by creating fictional holidays. While some of these are meant to be taken lightly, there are others that are far more serious in intent and presentation.

Whacking Day - The Simpsons

Homer whacking on Whacking Day in The Simpsons

There’s no question that The Simpsons is one of the best animated series ever made, and its influence on popular culture has been enormous. In one of its best episodes, it presents the fictional holiday of Whacking Day, in which snakes are slaughtered wholesale by the inhabitants of Springfield. Obviously, Lisa plays a key part in doing away with this barbaric practice, and the episode uses the holiday to provide the sort of insightful cultural and social commentary that has always been one of the greatest strengths of the show.

Freedom Day - Futurama

Bender and Nixon in Futurama

Futurama may not have achieved quite the enormous success of The Simpsons, but it should still be seen as one of Matt Groenig’s best creations. In part, this stems from its ability to create scenarios that are uproariously funny, such as Freedom Day.

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As its name suggests, it is a holiday focused on giving celebrants the freedom to do anything that they want without consequence. Of course, there actually are consequences in this case, and hilarity ensues, including an all-out invasion from the Decapodians. As always in Futurama, even a minor event can have major consequences.

Colonial Day - Battlestar Galactica

The cast of Battlestar Galactica posing for a photo

Battlestar Galactica is rightly regarded as one of the best science fiction series in the history of television. It has a thematic and philosophical richness that sets it apart from many of its fellow dramas, and it repeatedly draws attention to political and social issues. Part of what makes the series so compelling is the extent of its world-building, as the presence of a holiday known as Colonial Day makes clear. In this case, the holiday marks a significant anniversary, namely the signing of the Articles of Colonization, which helped to ensure the survival of the human race

First Contact Day - Star Trek

Star Trek First Contact Day Children of Mars

There’s no question that Star Trek is one of the most influential television series in the history of the medium, and it has spawned many movies and television series. As with so many other science fiction series, what makes it so compelling is the extent of its building of its alternate world. As its name suggests, First Contact Day commemorates the moment when humans and Vulcans first openly met. Unsurprisingly, this event would come to have tremendous political consequences for the entirety of the human race.

Galentine's Day - Parks And Rec

Leslie celebrating Galentine's Day on Parks and Recreation

Parks and Recreation is one of the best feel-good sitcoms, and it is full of characters who genuinely care about one another and want to make the city of Pawnee a better place. It is unsurprising that the ever-optimistic Leslie Knope would have developed her own holiday, Galentine’s Day, which is meant to celebrate the extraordinary friendships that often exist between and among women. It’s a sign of just how much her friends and her family – particularly Ann Perkins and her mother – mean to Leslie and how crucial they are to her happiness.

Festivus - Seinfeld

Festivus dinner in "The Strike"

Though the holiday Festivus was invented by the author Daniel O’Keefe, it came to national attention and fame when it made a memorable appearance in the hit sitcom Seinfeld. In one of the funniest episodes, Kramer and Frank Costanza decide to resurrect its celebration.

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Given that this is Frank Costanza, the holiday includes a number of elaborate and abrasive traditions, including most notably the airing of grievances. It remains one of the funniest holidays in the history of television, and a reminder of why Seinfeld itself remains so enduringly popular.

Merlinpeen - 30 Rock

Frank wearing a hat that says Kung Fu Beech in 30 Rock

30 Rock is arguably one of the best sitcoms of the 2000s, and Liz Lemon remains one of Tina Fey’s best characters. Among the many humorous elements of the series, it also features the creation of a fictional holiday, Merlinpeen, which is invented by several other characters on the spot. It is obviously not to be taken literally, but they still deserve credit for leaning so much into the creation of this fictional celebration, even though the whole affair does give Kenneth a bit of a crisis of faith.

Robanukah - Futurama

Bender holding a bottle of alcohol in Futurama

Futurama has the distinction of being one of the series that has more than one fictional holiday as part of its story. It’s not especially surprising that, in this case, the holiday in question is in fact the creation of Bendr. Titled Robanukah, it is, according to the irascible robot, one of the most important days in the robot calendar. As is so often the case with this character, however, it seems as if it’s little more than an excuse for him to avoid working.

Cinco De Cuatro - Arrested Development

Michael and Lucille 2 in Arrested Development

Lucille Bluth is arguably one of the best characters to have appeared in a sitcom, and she deserves a great deal of credit for helping Arrested Development to become the phenomenon it was (and is). Among some of her more dubious accomplishments is the creation of the holiday Cinco de Cuatro, which was essentially designed to make the celebration of Cinco de Mayo impossible for the Latino residents of Newport. Unsurprisingly, it backfired, and the day would go on to become a notable one for several members of the family.

Unification Day - Firefly

The Serenity crew in Firefly.

Firefly is another science fiction series that, despite its very short time on the air, still managed to establish a strong reputation for itself. The fictional holiday Unification Day was an important part of the series’ internal lore, as it marked the anniversary of the end of a long-running war between the Independents and the Union of Allied Planets. As is so often the case in science fiction, this particular holiday helps to add texture to this fictional world.

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