Queen Elizabeth II
Queen Elizabeth II honored the Americans that died following the 9/11 attacks on Sept. 11, 2001. Pictured: The Queen marks the centenary of GCHQ (Government Communications Head Quarters) at Watergate House on February 14, 2019 in London, England. Getty Images/Hannah McKay-WPA Pool

Queen Elizabeth II reportedly broke a 600-year-old tradition following the U.S. terror attacks on Sept. 11, 2001.

In the Amazon Prime documentary “The Queen’s Diamond Decades,” it was revealed that Her Majesty decided to change the traditional Changing of the Guard ceremony to include the Americans. Patricia Hodge, the narrator of the documentary, said, “The following morning in London, the Queen broke with tradition to show solidarity with America. They’ve never done it like this before.”

The American national anthem was played during a special ceremony to strengthen the relationship between the United States and the United Kingdom. It was also the first time that the monarch allowed the troops to play the American national anthem.

Approximately 5,000 people – most of whom were Americans – gathered outside Buckingham Palace in the wake of the attacks. Prince Andrew was also there to lead the troops in a formal salute.

According to The Telegraph, beside the Duke of York was William Farish, the American ambassador to Britain. Farish was spotted putting his hand on his heart during the ceremony.

“The band then played a selection of somber American music, including ‘Hymn for the Fallen,’ written by the composer John Williams and used in the final credits of the film ‘Saving Private Ryan,’” the publication reported.

Later that week, the Queen attended a service of remembrance in London for the victims of the terror attacks. She was photographed with tears in her eyes as she left St. Paul’s Cathedral.

The 9/11 attacks resulted in the deaths of 2,977 people in New York City, Washington, DC, and outside of Shanksville, Pennsylvania. The attack was orchestrated by al Qaeda leader Osama Bin Laden, according to CNN.

At the World Trade Center site in Lower Manhattan, 2,735 people were killed when the hijacked American Airlines Flight 11 and United Airlines Flight 175 were intentionally crashed into the north and south towers of the building.

Two months after the attack, the U.S. government released a tape wherein Bin Laden took responsibility for what happened.