Happy birthday, Britney Spears! It's been a huge year for the singer, who won a legal battle to end the conservatorship that ruled for life for 13 years and got engaged to her longtime boyfriend Sam Asghari. Now she's ringing in the big 4-0 — and no, we can't believe it either! To celebrate the singer's big day on Dec. 2, 2021, Wonderwall.com is taking a walk down memory lane and reliving Brit's most fantastic retro fashion moments from early in her career… Let's start with this look… A pregnant Britney hit the "Charlie and the Chocolate Factory" premiere in Hollywood in July 2005 wearing a silky chocolate brown skirt with a baby blue tank top that read "I have the Golden Ticket" and an arrow pointing at her belly. Two months later, she gave birth to her first child, son Sean Preston Federline.
Keep reading to see more of Britney's most amazingly retro looks…
Did she forget something?! Britney Spears donned a purple sweater and pink strappy heels — but appeared to be pantsless — at the UPN TCA Summer Press Tour in Pasadena, California, in July 2001.
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Britney Spears wore this eye-popping ensemble to the 2000 Billboard Music Awards in Los Angeles. With her fancy fedora, sprawling choker, orange-and-purple coat dress with a matching push-up bra, fishnet stockings and a peekaboo glimpse of her belly button piercing, this dizzying look had a little something for every taste!
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Ah, young love! In this very '90s satin slip dress, Britney Spears looked like she was ready for a slumber party with boyfriend Justin Timberlake when they attended the Family Celebration Benefit in Los Angeles in April 2001.
Britney Spears rocked a strapless black dress, long gloves, a choker, dark pantyhose and a fascinator at the 2003 Glamour Magazine Women of the Year Awards in New York City. We love an LBD as much as Britney does — but this outfit skewed more '50s cocktail party than 21st century red carpet.
With her embellished shirt, cropped pink jacket and floor-grazing, multi-pocketed bootcut jeans, Britney Spears was like a walking ode to old-school style trends when she received her star on the Hollywood Walk of Fame in November 2003.
Britney Spears attended Pepsi's NFL Kickoff Live event in Washington, D.C., in September 2003 in cropped pants, ankle boots, a cropped vest, fingerless gloves and a blonde bob with streaks of pink. We admire her confidence!
Who knew they were friends!? Britney Spears opted for a familiar silhouette — a sleeveless top and low-slung pants — when she and Natalie Portman hosted a New Year's Eve party at Ian Schrager's Hudson Hotel in New York City in 2002.
A young Britney Spears struck a playful pose in May 1999 wearing a look that she would end up riffing on throughout her career: a midriff-baring top and hip-hugging pants. How cute was she?!
She was that innocent! Britney Spears kept it totally ladylike in a black strapless dress, a purple wrap and a black patent handbag at the 1999 MTV Europe Awards in Dublin.
Britney Spears had her very own Marilyn Monroe moment, complete with iconic halter dress and blond curls, at a belated 28th birthday party for her then-husband, Kevin Federline, at an Atlanta nightclub in March 2006.
Britney Spears attended the premiere of her movie "Crossroads" in Los Angeles in February 2002 in a barely-there slip dress, choker, skin-tight denim and tall stiletto boots.
Britney Spears looked prom-worthy in this purple strappy number and delicate white shawl at the 1999 Billboard Music Awards in Las Vegas. All that's missing was the corsage!
Just four months shy of her 21st birthday, Britney Spears strapped on head-to-toe leather at the MTV Video Music Awards in New York City in August 2002. From the top of her black cap to the tips of those lacy stilettos, the all-grown-up star looked like she meant business!
At the 2003 MTV Video Music Awards in New York City, Britney Spears' lacy minidress and piles of accessories were an homage to Madonna's iconic "Like a Virgin" outfit — for good reason. The two megastars performed together at the show… and made global headlines when they locked lips on stage!
It doesn't get much more wonderfully retro than this! Britney Spears and Justin Timberlake were unforgettable — literally — when they attended the 2001 American Music Awards twinning in head-to-toe denim looks.
Red alert! Britney Spears showed how well she cleans up in a slinky crimson gown, delicate jewelry and voluminous curls at the 44th Annual Grammy Awards in Los Angeles in 2002.
So dark! Britney Spears hit the Baby Phat show during the Mercedes-Benz Fashion Week Fall 2007 presentations in New York City wearing an all-black ensemble and dyed raven hair to match.
A beaming Britney Spears chose a baby doll dress for the Teen Choice Awards in Los Angeles on Aug. 20, 2006 — just 23 days before she gave birth to her second son, Jayden James Federline!
Britney Spears showed off her famous tummy in a semi-sheer ensemble (with strategically placed feathers) and black trousers at the 1999 MTV Video Music Awards in New York City.
A nod to her Louisiana roots? Southern belle Britney Spears paired her chiffon minidress and tassel belt with cowboy boots at Nickelodeon's 16th Annual Kids' Choice Awards in Los Angeles in April 2003. (As for what appears to be garter belt around her arm: Why ask why?)
Britney Spears was in the (comfort) zone when she wore a cropped asymmetrical halter top, tight pants and a fedora for the premiere of the movie "The Four Feathers" in Los Angeles in September 2002.
Britney Spears looked sweet — and so very '90s! — in head-to-toe pink including sequined pants at the 1999 Teen Choice Awards in Los Angeles.
Sheer bliss! Britney Spears wore her sunglasses at night and donned a see-through top, hot pants and stockings to hit the club with friends in Los Angeles in June 2007.
Britney Spears let her hair down in a blue strapless dress with a ruffled bottom at the 12th Annual Screen Actors Guild Awards After Party, hosted by People magazine and the Entertainment Industry Foundation, in January 2006.
A vision in purple! Britney Spears was a monochromatic marvel when she hosted a party at London's Planet Hollywood in November 2000 to celebrate the end of her "Oops!… I Did It Again Tour."
Britney Spears changed things up and rocked a little white dress and super-long blonde locks at the grand opening of LAX Nightclub at the Luxor Resort & Casino in Las Vegas in September 2007.
She's got the look of love! Britney Spears went for a lacy, low-cut dress when she stepped out with boyfriend Justin Timberlake at the 29th Annual American Music Awards in Los Angeles in January 2002.
Oops! She did it again. Britney Spears went for her trusty old LBD and choker combo at the Scandinavian Style Mansion in Los Angeles in December 2007.
Britney Spears confidently rocked a leather-and-lace look in April 2002 at the Australian premiere of her film "Crossroads" in Sydney.
Was she trying to distract from K-Fed's hairstyle? Britney Spears chose a shiny brocade coat and a messy updo for a night out in New York City with husband Kevin Federline in November 2005.