LONDON — Eleven days after the arrival of Archie Harrison Mountbatten-Windsor, the royal tyke’s birth certificate has been released — and a mystery solved.

Brace yourselves: Baby Archie was born in a hospital.

A shocker, we know. Queen Elizabeth II's eighth great-grandchild did not arrive in a bathtub at Frogmore Cottage on the Windsor Castle grounds, as tut-tutting royal correspondents had previously speculated.

Rather, Archie was born at Portland Hospital, an American-owned, upscale, private medical center in London's Westminster neighborhood on the morning of May 6.

The specific where and how surrounding the birth of the son of Prince Harry and Meghan, Duchess of Sussex, had been matter of great interest because:

1. Harry and Meghan, the palace warned, had made “a personal decision to keep the plans around the arrival of their baby private.” So royal watchers kind of freaked out.

2. Meghan is a feminist, an American from California, and so it was rumored/reported in the British press that she wanted to have a home birth (audible tsk-tsking), with a helping hand from a midwife, not a bunch of “men in suits.” (Didn’t matter that most British mums have babies with midwives).

3. This broke recent protocol, set by Harry’s older brother Prince William and his wife, Catherine, Duchess of Cambridge, who dutifully had their three heirs in the maternity wing at St. Mary’s Hospital in London — and then appeared a few hours later to pose before the global cameras with the newborns.

There was one other kind of cool thing about the birth certificate.

It lists the mother’s name as “Rachel Meghan Her Royal Highness The Duchess of Sussex.”

And then for occupation? “Princess of the United Kingdom.”