Kate Middleton and Prince William
Kate Middleton and Prince William broke a centuries-old royal tradition with their modern courtship. Pictured: Prince William and Middleton attend the EE British Academy Film Awards at Royal Albert Hall on Feb. 10, 2019 in London. Getty Images/Tim Ireland

Kate Middleton and Prince William broke centuries-old royal protocol when they were still dating.

The Duke and Duchess of Cambridge have been married for over seven years already. Although they are more reserved when it comes to public display of affection compared to Prince Harry and Meghan Markle, they set the precedent of modern courtship.

Prince William and Middleton lived together before they got married. According to Katie Nicholl in her 2017 book “Harry: Life, Loss and Love,” the couple made an unprecedented move by deciding to live under the same roof.

“In a breach of royal protocol that showed just how modern their courtship was, he and Kate were living together in a rented cottage close to William’s [RAF] base,” Nicholl wrote.

Royal couples living together before marriage was previously unheard of. Princess Diana only moved into Buckingham Palace after her engagement to Prince Charles was announced and at the time they still lived in entirely separate suites in the palace.

Prince William and Middleton didn’t deny that they lived together before their engagement. The couple met at St. Andrews University and lived in a dorm.

“We moved in together as friends and then because we were living together – we lived with a couple of others as well – and it just sort of blossomed from there really,” Prince William said during their engagement interview.

During the same interview, Middleton asked Prince William if he liked her cooking and the royal prince teased her by replying that her skills in the kitchen had gotten better.

Nicholl also pointed out how Middleton reacted differently compared to Prince Harry’s then girlfriend Chelsy Davy about the royal brothers’ commitments.

“While Harry’s military commitments had taken their toll on his romance with Chelsy [Davy], Kate was prepared to make sacrifices that Chelsy simply wasn’t,” the royal biographer added.

Middleton was reportedly “taking on, and enjoying, life as an ‘RAF wife.’” While Prince William was away for training, Middleton spent her time taking photographs and working at her parents’ party-planning business.

There was reportedly a time when Queen Elizabeth II had a “grave concern” about Middleton’s antics. Prior to her engagement with Prince William, the duchess had no full-time job and was always partying. Middleton was very hurt with the early criticism of the monarch about her lifestyle but she didn’t talk back to her about it.