The Royal Family has undergone significant changes in recent weeks following the death of Queen Elizabeth II on 8 September.
With a new monarch on the throne, the family's line of succession has shifted, and so too have their royal titles. From Philip Mountbatten to Princess Charlotte of Wales, we take a look at the origin of royal surnames, how they've evolved and why they're rarely used by the royal family.
WATCH: Royal family return to normal duties as mourning period ends
What's the history behind royal surnames?
Royal surnames only came into existence after 1917. Before then, members of the British royal family would employ the name of the house or dynasty to which they belonged, such as Hanover - i.e., Queen Victoria of the House of Hanover.
Kings and princes were historically known by the names of the countries over which they and their families ruled, meaning that they signed themselves by their first names only. This ancient tradition remains intact to this present day.
Queen Victoria was born into the Royal House of Hanover
Historically, sovereigns would take the name of their 'House' from their father - much in the same way as children inherit their father's surname. Queen Victoria's eldest son Edward VII belonged to the House of Saxe-Coburg-Gotha.
Following the outbreak of the First World War, George V nonetheless ditched the royal tradition and changed the family's name to Windsor. This radical change occurred as a result of strong anti-German sentiment.
George V introduced a major change
The decision was supposedly triggered by public anger at air raids over London, especially the bombing of a school in the East End. On 13 June 1917, the Germans carried out daylight raids, with one attack killing 18 children. Coincidentally, the bombers used to carry out these devastating attacks were called Gotha IV bombers - the same name as the royal family.
Which surname do the Queen's descendants use?
Although Queen Elizabeth II confirmed 'Windsor' as the royal family surname when she ascended the throne in 1952, she wanted a separate name for her own direct descendants to better reflect her marriage to Prince Philip.
After eight long years of deliberation, the Queen and Prince Philip managed to reach a compromise. In 1960, it was therefore declared in the Privy Council that the Queen's descendants, other than those with the style of Royal Highness and the title of Prince/Princess, or female descendants who marry, would carry the hyphenated name of Mountbatten-Windsor - Mountbatten being Prince Philip's surname upon marring the Queen in 1947.
Queen Elizabeth and Prince Philip reached a compromise
For the most part, members of the Royal Family who are entitled to the style and dignity of HRH Prince or Princess do not need a surname, but if at any time any of them do need a surname (such as upon marriage), that surname is Mountbatten-Windsor.
The name is still in use today thanks to the late monarch's grandchildren and great grandchildren. Lady Louise, James, Viscount Severn, Archie Harrison and Lilibet all use Mountbatten-Windsor as their royal surname. Unless King Charles decides to shake things up, the late Queen's very personal moniker will continue to run in the family through the male line.
What about titled members of the royal family?
"Members of the Royal Family can be known both by the name of the Royal house, and by a surname, which are not always the same," the official royal website reads. "And often they do not use a surname at all."
Titled royals don't typically use surnames
Members of the Royal Family can also use a last name from their family's official title. For example, Prince Harry and Prince William were known at school and in the military as Harry Wales and William Wales, a surname that derived from their father's official title.
How have Prince George, Princess Charlotte and Prince Louis' names changed?
In his first address as monarch on 9 September, the royal said that he wanted his oldest son, to be known by his own previous title the Prince of Wales and Kate would become the Princess of Wales, which was last used by William's late mother Princess Diana.
Prince William and Princess Kate's children have a new surname
Formerly known as the Cambridge children, Prince George, Princess Charlotte and Prince Louis are now known as the Wales'. News of their name change was first announced in the King's first speech and their new names first appeared in print in the order of procession for the Queen's funeral.
The young royals now use Wales as their surname
Despite this major change, it is not known whether the young royals have updated their surnames at school. George, Charlotte and Louis all enrolled at Lambrook on the exact same day that their great-grandmother, the Queen, died. It seems likely that they have since switched to Wales after initially enrolling as Cambridge.
What about first names?
Picking a baby name for your newborn is tricky at the best of times. Add royalty into the mix and the challenge is even greater! Steeped in tradition, the British royal family have a long history of selecting traditional names.
Princess Kate perfectly summed up the immense pressure she felt when it came to naming her children. During her visit to the Royal Surrey County Hospital, Kate revealed picking their names "felt like quite a big pressure" because "the world was waiting for them to name their children". The Princess of Wales later revealed she simply decided to use her "favourite names".
Prince Charles played a part in picking Zara's name
In recent years, the royal family have veered away from stereotypically regal names in favour of more modern monikers. Prince Charles supposedly came up with the name Zara after she came into the world "rather suddenly" and Prince Harry opted to use the Queen's nickname 'Lilibet' for his only daughter.
Although it's not essential for members of the royal family to seek permission from the monarch, they are nonetheless expected to heed their advice.
The royals select meaningful middle names
With regards to middle names, the royal family typically include multiple names as a way to pay tribute to their relatives. In honour of Lord Mountbatten, Kate and William used Alexander and Louis for their eldest son Prince George.
Prince Harry and Meghan opted for Diana as Lilibet's middle name and both Princess Beatrice and Zara selected Elizabeth as middle names for their respective daughters, Sienna and Lena.
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