The Queen's guards are playing the theme from HBO's hit Original Series "Game of Thrones" and not Queen Cersei, Margaery, Daenerys or any other Queen of Westeros and Essos but the Queen of the United Kingdom, Queen Elizabeth II.
In an interesting twist to the usual "Changing of the Guards" ceremony that takes place at Buckingham Palace, the Queen's official residence in London, the Royal Guards were filmed by tourists playing the theme to Game of Thrones to accompany the popular ceremony which is witnessed by millions of people who come from all over the world. The Irish regiment was responsible for the Westerosi tribute and there is no official statement from Buckingham palace about how the Queen feels about this break from tradition.
The Game of Thrones theme song has become a familiar tune to fans of the show as a lengthy version of it is played at the start of each episode while animated graphics travel through a map to introduce the locations of important places in the fantasy world conceived by author George RR Martin from whose books the series is based.
Many of the scenes for the series have been filmed in the UK particularly in Northern Ireland. At the moment, filming for season 5 is in progress and just last week, several photos have emerged on social media from fans who were able to visit the filming sites particularly those in Portstewart Strand in Northern Ireland which is believed to be the location for shooting the Southernmost province of Westeros called Dorne. Members of the Night's Watch such as Kit Harrington who plays Jon Snow has also been spotted in Belfast along with other cast members.
Earlier this year, Queen Elizabeth herself visited the "Game of Thrones" exhibition in Northern Ireland along with several cast members. The exhibition has gone to several cities around the world to showcase props, costumes and other interesting merchandise that were used in the series to be viewed up close by fans of the show.