Madonna shared an Instagram selfie from her birthday party on Aug. 17, 2013. Credit: Courtesy of Madonna

Once a Material Girl, always a Material Girl. Madonna celebrated turning 55 in a fashion befitting the famously dramatic, often outlandish pop star -- that is, with an over-the-top French Revolution-inspired costume bash in the South of France on Saturday, Aug. 17!

The guest of honor channeled, naturally, Marie Antoinette, the Gallic country's last queen who memorably said "Let them eat cake!" before later meeting her demise at the guillotine. Fit and fabulous, Madonna wore a gold and diamond grill on her teeth, a heart-shaped eyepatch over one eye, an enormous teased blond wig, a purple, cleavage-baring corset leotard -- and no pants! "Madonna looked amazing! Her legs are sick!" a source tells Us Weekly.

Boyfriend Brahim Zaibat, daughter Lola, 16, and son Rocco, 13, partied with the fun-loving mom of four. "They danced to Madonna songs, the whole family. It was cute. Everybody was dressed up and Madonna kept flinging around a white rose," says the source. "Lola is growing up and had a birthmark above her like lip just like her mom as a little tribute, and she wore a tight-fitting bodice, too."

The singer shared a close-up shot of her lavish look on Instagram the next day, writing: "Perhaps we had too much Cale! But at my Birthday Party all I could see was LOVE." She followed that picture with a similar photo that was captioned, "Perhaps I had too much Champagne! I meant to write CAKE!"

This isn't the first time Madonna has dressed up in an outfit inspired by that French period. In 1990, the singer wore the ball gown donned by Glenn Close in 1988's Dangerous Liaisons for her performance of "Vogue" at the MTV Video Music Awards; and for her Re-Invention tour in 2004, the singer rocked bustier leotards similar to the one she wore to her 55th birthday bash.