Now for this year's styles:
We'll start with the queen. Lime green everything and strings of pearls. Queen Elizabeth II's hat was embellished with all kinds of fanciful feathers and jewels.
Markle's mother bought into the British style with a subtle, classy pistachio dress by Oscar de la Renta. Her matching hat pulls it together. And then there's Camilla, the Duchess of Cornwall. She tends to let her hats do the most.
Okay, but really, Camilla?
Apparently, the purple item on Countess Spencer's head in the shot below is called a “bow disc.” Rachel Trevor Morgan, an haute-couture designer who creates hats for the royal family, is responsible for this delightful headpiece.
Tennis star Serena Williams opted for a subtle, flattering fascinator that matches her pink dress.
Amal Clooney, an international human rights lawyer, went for something that seems to fall in between hat and fascinator. Whatever it is, it's great.
Actor Abigail Spencer opted for a navy blue fascinator while her friend Priyanka Chopra, also an actor, decided on a large purple hat.
Oprah Winfrey did not just got for a hat. She went for a wide-brimmed one with flowers and feathers that perfectly matches her pale lilac dress. Her friend Gayle King told CBS that when Winfrey arrived in London, she panicked that her dress was too white — and had a new one made overnight.
Oh, my. Lady Kitty Spencer, the 27-year-old niece of Princess Diana, stunned crowds with her Dolce & Gabbana dress and elaborate fascinator by Philip Treacy.
The Duchess of Cambridge wore a cream-colored dress and a fascinator that managed to be both subtle and festive.
And let's give it up for the regular old Brits who heard hats were the in-thing, and just wore the whole wedding on top of their heads.