Why the royals love their fascinators

The U.K.'s crème de la crème will be dressed in their finest as the world watches Prince Harry and Meghan Markle tie the knot at St. George’s Chapel on May 19.

Like anything else associated with the royal family, wedding attire follows a historic tradition. The most beloved tradition is likely the fascinator, a centuries-old headwear trend that the British love to wear at royal unions.

The headpiece likely dates back to the late 1800s when it was first mentioned in an Edith Wharton book.

“Literally a girl tied a scarf around her head to fascinate the attention of the men in the room,” Julia Knox, milliner and the owner of East Village Hats told “Good Morning America.”

Fascinators are still intended to grab the attention of the opposite sex, Knox said.

But, now, fascinators will grab the attention of the world, as spectators will try to grasp the dos and don’ts of the iconic accessory worn on the heads' of the guests at the royal wedding.

Guests who are close in age to the royal bride are likely to wear the more chic and whimsical fascinators, famously seen on Catherine, Duchess of Cambridge, and Princess Beatrice, Knox explained. Older generations, on the other hand, are more likely to wear highly textured and adorned hats.

The key to picking the right fascinator is simple, she explained.

“It’s the royal wedding. You’re not supposed to be making it all about you,” Knox said. “If your hat is getting more attention than the bride, you’ve gone too far.”