A common staple in fiction and in Real Life. There are always parties which are centered around certain decades which remain firmly in the minds of people (who may or may have not lived such decades) and popular culture. Such parties are usually based around music, fashion, dance styles and/or movies of a decade. The most popular ones tend to be The Roaring '20s, The '50s and The '80s. The '60s and The '70s are also popular choices, primarily during The '90s and The Oughties respectively, with these decades being irony fodder.
This celebration of the past might come from the use of a Nostalgia Filter. As people grow older, they start to miss their youthful days, where things seemed a lot simpler and, well, fun. Hence why these parties are usually organized. Nostalgia is connected to the need of escapism and the need of reminding what you've left behind, from things like clothes to old friends. However, people also tend to celebrate decades they barely or even haven't lived through just because the fashion seems more appealing or glamorous.
- The cover of one Archie's Double Digest from the 2000s had the gang at a "retro party". Based on the clothes Betty and Veronica turned up in, we assume the party's organizers had The '70s in mind, but Archie shows up in a caveman costume, calling it "the ultimate retro look."
- The Fabulous Furry Freak Brothers: A comic from the 1970s had the guys throwing a '50s-themed New Years party. Franklin is a holdout, declaring the decade "a drag", and as the story recalls their real '50s party some 15 years earlier, with its reckless drunkenness, sexual frustration, and violent, destructive juvenile delinquents, they decide to have a naked sex-and-drugs '60s-themed party instead.
- From the 2002 Australian comedy Crackerjack about the elderly members of a lawn bowls club.
"How about we have a fancy dress party, and we all come dressed like our favourite decade?"
"We tried that before, and everyone dressed like the Fifties."
- Never Been Kissed: Discussed. The kids wants to have a "Millenium" themed prom but it turns out another high school does that as well and they want to be unique. Their teacher suggests an '80s prom but they boo to that idea. (They choose "famous couples throughout history" after all.)
- The Locals: Because of the way they are dressed, Grant and Paul assume that Kelly and Lisa are on their way to 80s themed party and accept their invitation to follow them. They later learn that the girls had died on their way to a party in the 80s, and are still wearing the clothes they were in when they died.
- Exaggerated In John Brunner's Stand on Zanzibar, since this is updated to a "Twentieth Century Party". The confusion about whether 2000 C.E. counted as Twentieth Century or Twenty-First was referenced, one of the few predictions the book got right.
- In A Boy Made of Blocks, Isobel invites Alex to a party based on The '60s. Alex wears a suit that makes him feel like Austin Powers.
- An episode of House features an "80's Party". Dr. House comes dressed in late 18th/early 19th century garb because the invitation just said 80's, and didn't specify a century. Doubles as an Actor Allusion due to his role as the Prince Regent in Blackadder.
- There's an episode centred around an 80's party in Hellcats.
- In an early episode of 2 Broke Girls the girls are kicked out of a late night laundromat because the laundromat is the location for an 80s themed rave/party with special guest VIKI from Small Wonder. Max is unironically pissed at being too poor to attend. She loved Small Wonder.
- The Red Dwarf episode "Balance of Power" has a flashback showing the characters at a party with a sign on the wall saying "Nostalgia Night 1990s". (The scene is set in the 21st or 24th century, depending on the Retcons.) The so-called '90s themed party looks like a cross between The '70s (for example, the disco ball) and The '80s (for example, the extravagant, campy clothes). Such cues and many more were taken from said decades because the episode itself was made in 1988.
- Several episodes of The Vampire Diaries have featured the main characters attending high school dances themed after certain decades (called Decade Dances in-universe).
- In Kath and Kim, Kath arrives in her everyday's clothes (which she hasn't changed since The '80s) to an 80's themed party.
- The Charmed episode "Muse to My Ears" has a minor subplot of a party being thrown at P3, and Piper getting annoyed that the client wants a theme. Paige suggests a 1940s theme, and the climax of the episode takes place at the party. The Stinger has Phoebe and Cole dressing up and dancing to period appropriate music.
- An episode of Perfect Strangers had Larry and Balki throw a 50's themed party where one of the guests was a hypnotist. He tried to hypnotize Larry into thinking he was Elvis, but wound up hypnotizing Balki instead.
- Midsomer Murders: In "Dance with the Dead", the village of Morton Fendle is obsessed with the now disused WWII airfield based there. They hold a 1940s themed dance that the Barnabys and Jones attend.
- Brooklyn Nine-Nine, "The Tattler": Jake and Gina go to their 20-year Class Reunion with a dress code and a theme from their high school days. Jake and Gina revisit their DDC style, which means the Dope Denim Crew. They have baggy denim hoodies. Jake's wife Amy wears a cute floral dress, a pair of Doc Martens, a black choker and a small backpack. Jake's friend from their ska band is implied to wear '90s outfits all the time.
Jake: Our 20-year high school reunion is tonight, and the party is '90s-themed, so we're dressing the way we did back then, AKA hella fresh.
- Gilmore Girls: Played for laughs. Rory attends a 2002-themed party which Olivia throws for her friend Lucy's birthday. The episode is set (and aired first) in 2007.
- The Saturdays' video for "Disco Love" has the group cycling through three decades. First is an outdoor gathering in the 70s, second is a roller disco in the 80s and finally a rave in the 90s.
- The Wotch had a 1970's themed dance (which annoyed Mingmei because she hadn't enjoyed the decade the first time around).
- CollegeHumor, "Realistic 80s Costume Party": Janie and Raph attend an 80s dress up party. Janie is excited because she loves popped collars, big 80s hair, dancing to music heavily relying on synthetizer and wearing leggings, but it turns out others find her generic costume offensive because literally millions of girls lived in the 80s.
- In Daria's episode "Life in the Past Lane", Jane is dating Nathan who is obsessed with swing dancing and the styles and manners of The '40s. They go to a dance party and to a drive-by cinema meeting centered around said decade.
- King of the Hill: In "Strangeness on a Train", Peggy plans her birthday party on a train: a murder mystery theatre train ride combined with 70's disco theme. Hank is not sure it's such a great idea, especially the disco part, but agrees with it to make Peggy happy. Their friends show up in their disco outfits, as well as most of the actors (but those have also costumes for their roles in the play). Many things go wrong with Peggy's party. The episode ends with a small impromptu disco-themed party at a random bar. The bartender hangs up a disco ball and finds an appropriate soundtrack. Peggy's friends dance in their disco outfits.
- The Simpsons:
- Marge's Old Flame Artie Ziff tries to woo her back by recreating their prom and paying everyone in town to dress like they did in The '70s. (Disco Stu, of course, "is working pro bono.")
- One episode has Greaser's Cafe, which is built around this trope (concerning The '50s, to be specific.) The owner boasts that in there, the fifties will never go away. Soon thereafter, the cafe has to close down.
- Just google the words of the title. There'll be hundreds of matches for all kinds of decade parties, especially from The '80s, which is likely to be the one easiest to represent visually. For some reason or another, these tend to be about the pop culture of 30 years earlier.
- Buffalo, New York's "World's Largest Disco," an annual seventies themed party that revolves around thousands of people dressing up in fashions from 1970s and turning a major metropolitan convention centre into one gigantic convention hall sized disco.