Jackie Kennedy was undeniably a fashion icon, even before she became First Lady.

It’s a hat that Catherine, Princess of Wales has frequently worn.

Kate has worn a more classic silhouette of the pillbox in multiple colors as well often matching her coat.

Kate Middleton smiling at Wimbledon

The accessory makes any outfit a stunner.

Jackie Kennedy, ever the fashion plate, made the sheath dress one of her go-to outfits.

Catherine, Princess of Wales often wears form-fitting sheath dresses, accentuating her slim waist without being revealing.

Kate Middleton wearing a green pillbox hat

Kate Middleton at the BAFTAs

Kate Middleton smiling

Kate Middleton and Prince William sitting on a bench in front of the Taj Majal

Kate Middleton smiling