Ever since the Queen's death was announced last Thursday, TV broadcasters and contributors have been appearing on screen dressed in all-black attire to show their respect to the late monarch.
And following King Charles' declaration of a period of national mourning, that will last until one week following Her Majesty's funeral on September 19, the Royal Family has also been sticking to an all-black dress code.
Last weekend the Prince and Princess of Wales, and the Duke and Duchess of Sussex greeted mourners outside Windsor castle, all wearing dark-hued clothes, and the King and Queen Consort and other members of the Royal Family also adhered to black clothing as a mark of respect.
Ordinarily, black is rarely worn by members of the Royal Family, who prefer to reserve the colour for periods of mourning, one exception being Remembrance Sunday, another a sombre occasion.
For Monday's funeral, according to Debrett's, certain members of the Royal Family will be expected to wear black, as per the strict dress code observed at state funerals.
"An all-black formal dress code is always respected. Ladies wear black knee-length dresses, or coats, black hats, and may also wear face-covering veils," the site explains.
Male mourners, on the other hand can either: "wear military attire, or – as was the case at the funeral of the Duke of Edinburgh – black morning coats with medals."
There's little doubt that black has become custom attire for funerals and periods of mourning, and of course the current period of mourning for the Queen is no exception, but where does the tradition stem from?
Why do we wear black to funerals?
Historians have traced the very earliest tradition of wearing black at funerals to the Roman Empire, when a person's death would be marked by switching a normally white toga for a black one.
More recently, the tradition of wearing black at funerals, in the UK at least, is believed to have been inspired by Queen Victoria.
"The colour black has long been connected with death however the tradition of wearing black at the time of mourning is strongly believed to have become fashionable in the time of Queen Victoria," explains Jeremy Field, managing director of C.P.J. Field, funeral directors who arranged the funerals for Queen Victoria and the Duke of Wellington.
"She famously wore only black following the death of her consort Prince Albert."
According to a blog post by Kirsty Salisbury, end of life worker and podcaster, when Queen Victoria's beloved husband Prince Albert died in 1861, she wore black at the funeral, and continued to wear black mourning veils for the remaining 40 years of her life.
As the monarch was considered something of a style icon, the British upper-class aspired to be like their Queen, adopting her clothing choices when in mourning as something of a status symbol.
Eventually, during the Victorian era, black clothing during periods of mourning became common practice, with official rules brought in specifying how long black attire should be worn for.
"After that, widows were regularly seen in black for one-two years after the death of their spouse," adds Field.
"A significant proportion of the ritual and ceremony still observed in funerals is derived from the Victorian period."
It is a tradition still largely practiced today thanks, in part, to the colour's association with sombre feelings.
"The colour black can be reflective of the desolation we feel when someone we love dies," Field explains.
"To some, it can feel wrong to seem exuberant in such circumstances. Wearing black or sombre clothes signifies that the wearer is in mourning and would appreciate patience and kindness."
Exceptions to the all-black rule
Of course, while black remains the traditional colour of choice for many mourners, some funerals across the UK are becoming decidedly more colourful.
"While it has been seen over time to be a sign of respect to avoid colourful clothing to a funeral and around others who are grieving, fashions are changing, with the emphasis on trying to celebrate that the person has lived rather than mourn the fact that they have died," explains Field.
And one way of doing that is introducing more colour to the dress code.
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A recent survey, by Co-Op Funeralcare, revealed that over a third (37%) feel that funerals are generally too sombre and should be more uplifting.
With that in mind, over a fifth (22%) of respondents would like mourners to move away from traditional black attire, preferring attendees to dress in bright colours. This compares to only 13% who now prefer a darker dress code.
According to Marie Curie, this shift away from black could also reflect our increasingly multicultural society; in Hinduism, for example, white is the traditional choice of colour to wear to a funeral.
The Royal Family hasn't always stuck steadfastly to the all-black rule either.
In 1938, the Queen Mother wore a white dress to her mother’s funeral to counter the sombre mood of impending war.
"The ultimate masterclass in making mourning dress into a regal fashion statement came in 1938, when Queen Elizabeth's mother, the Countess of Strathmore, died weeks before a pivotal royal tour to France," Matthew Storey, curator at Historic Royal Palaces, told The Telegraph.
"More than a mere charm offensive, this was the king and queen's first foreign visit since the abdication of Edward VIII and came as the prospect of war loomed gravely over Europe. A black wardrobe simply wouldn’t do, as it was imperative to come bearing optimism."
And for Prince Philip's memorial service royals eschewed the traditional black to pay a touching tribute to the late Duke of Edinburgh by wearing the same shade of dark green, the late royal's livery colour.
Why TV presenters and Royals have black outfits to hand
It has been revealed that news reporters were able to change so quickly into black outfits, as presenters always have black outfits on standby for sombre occasions, such as the death of a senior royal.
Similarly, royals have to be prepared for possible tragedy when they travel overseas, packing a black outfit with them in their luggage.
This custom actually seems to have been put in place after the death of the Queen’s father, King George, in 1952.
When news broke that her father had died, the then-Princess was on a royal tour with Prince Philip in Kenya and was rumoured not to have a black outfit with her to arrive home in.
She reportedly had wait for it to be delivered directly to her plane when she landed back in the UK before she could disembark.
Since then, royals are thought to have been encouraged to pack a black outfit when travelling in case there is a death in the family or another sombre event, which they must be seen to show respect for.