Queen Mother broke an over century-old protocol when she joined the royal family.

In the 2018 documentary “The Queen Mother,” it was learned that Elizabeth Bowes Lyon, later known as the Queen Mother, broke almost 250-year royal protocol when she married King George VI and became the Duchess of York. At the time, there was a careful distinction between the royals and the different levels of aristocracy and princes and princesses were expected to marry other royal bloods.

“It doesn’t seem odd to us now but the fact she was a commoner and wasn’t a member of the Royal Family was really new and broke convention,” royal historian Alastair Bruce said of Queen Mother’s entry into the Firm.

However, the royal expert noted that King George V and Queen Mary adored the Queen Mother’s freshness and attitude. She had the “beguiling eyes and impish style.”

British biographer and historian Philip Ziegler agreed with Bruce’s observation. In fact, according to him, “it is probably true to say that the King liked his daughter-in-law almost more than any of his own children.” He added that the Queen Mother had a “very warm and charming presence.” She was also very respectful.

Queen Mother being the first commoner bride paved the way to Kate Middleton and Meghan Markle’s entry into the royal family. According to Martina Bet, a journalist for Express, if the royal family was still following hierarchical structures, it would be impossible for Prince William and Prince Harry to marry Middleton and Markle, respectively.

Both Middleton and Markle come from working class families which the monarchy standards consider as “commoners.” Middleton’s parents worked in aviation before launching their family business Party Pieces. On the other hand, Markle’s mother is a social worker and her father is a former television lighting director.

In related news, Markle successfully kept her wedding dress designer a secret until her big day. According to Angela Mollard, Middleton failed to do the same when she married Prince William in 2011.

Meghan Markle and Kate Middleton Kate Middleton and Meghan Markle attend day twelve of the Wimbledon Lawn Tennis Championships at All England Lawn Tennis and Croquet Club on July 14, 2018, in London. Photo: Getty Images/Clive Mason