When the Queen dies, all eyes will be on the new King, Charles, and on what he will do as monarch.
As he will finally get the job he has waited most of his life for, so his son, Prince William, will move up the ranks and become heir to the throne.
As heir he will have more responsibilities and duties, and will take on the Duchy of Cornwall.
The duchy is a parcel of land across the country, totalling 135,000 acres, and exists to provide an income to the heir to the throne, outside of the Sovereign Grant.
What is the Duchy of Cornwall?
The Duchy of Cornwall is a land estate covering 135,000 acres, which was first created in 1337 by King Edward III as a means for his son, Prince Edward, to have an income.
Although it’s named after Cornwall, it doesn’t mean the Duke of Cornwall owns the whole county. Cornwall is about 2% duchy land.
Watch: How Prince Charles makes his money
Charles has maintained a special relationship with the whole county, and makes regular visits. The duchy does have some rights related to the whole county, for example, it owns the coastline and riverbeds.
The revenue from the duchy goes to the Duke of Cornwall and he uses it to fund his personal and work activities.
It also helps fund the offices of the Duke and Duchess of Cambridge and used to fund the Duke and Duchess of Sussex’s office too.
What will Prince William have to do?
William will have a lot of new things to get to grips with when he takes over such a large estate.
He will find himself in charge of more than 150 staff members working across several offices, from London to Bath, the Isles of Scilly and Dartmoor.
He’ll also need to look after towns, like Poundbury, which were created by Charles.
But he has already been learning some of the ropes. In 2019, an ITV documentary showed how William was preparing for duchy life.
He met farmers from across the duchy estate and even moved his father close to tears with the passion and enthusiasm he showed for it.
He said he would do “much the same as what my father is doing” but with a “few tweaks”.
The court circular, which is the record of all the meetings and engagements the royals undertake, shows that William also has meetings with board members from the duchy.
From October 2019 to October 2020, he had five meetings with various representatives from the duchy, or with its committees.
Charles’s own “baptism of fire” with the duchy, as he put it, has almost certainly made him keenly aware of training his son in the essentials sooner rather than later.
It was in 2011 that William attended his first duchy meeting, with a Clarence House spokesman telling the Daily Telegraph: “He has been learning about the duchy for a number of years with a view to getting a greater understanding of how it all works.”
Duchy land includes things like holiday homes, ancient monuments, farm land, commercial property, new towns, a military training ground and the Oval cricket ground in London.
That’s on top of rural homes and land, and flats and houses.
Charles has started many of his own initiatives during his tenure at Duke of Cornwall too, like giving people from non-farming backgrounds the opportunity to have their own farmland.
Charles has a good reputation with lots of his tenants too, so William will have big shoes to fill.
William’s eldest son Prince George is likely to eventually be a working royal, so the duchy will probably fund his offices, as it funded William’s and Harry’s, once he becomes a full time royal.
Whether Charlotte and Louis also take on roles remains to be seen. Charlotte will be the third in line, so it’s more likely that she would, than her brother Louis.
But with Harry carving out a new role, and Charles’s desire for a streamlined monarchy, the exact nature of the younger siblings isn’t as clear.
What will William and Kate’s new titles be?
William will become Prince William, Duke of Cornwall, and Kate will be formally known as Catherine, Duchess of Cornwall.
But that doesn’t mean they will lose their wedding present from the Queen - their titles of the Duke and Duchess of Cambridge.
In 2011, the evening before their wedding, the Queen granted them the titles, and they will remain, and be added onto their new ones.
So together William and Kate would be Their Royal Highnesses, the Duke and Duchess of Cornwall and Cambridge.
Quite a mouthful.
Watch: Duchess of Cambridge pulls a pint in the Duchy of Cornwall
Will William also be the Prince of Wales?
Although Prince Charles has been both the Prince of Wales and the Duke of Cornwall, the two roles are actually separate.
The duchy is hereditary, so William will assume that as soon as the Queen dies.
But the title of the Prince of Wales technically merges with the crown on accession, and would have to be given specially to William by Charles.
The Queen bestowed the title of the Prince of Wales on Charles in July 1958 when he was nine.
He was invested as the Prince of Wales in a ceremony in Caernarfon Castle in 1969.
Because of Charles’s age, and some growing nationalism in Wales, he was sent to Aberystwyth University to learn Welsh. He then gave his investiture speech in Welsh, and speaks it on occasion to this day.
William, by contrast, was not anywhere near the throne when he was at university, and went to St Andrews University in Scotland.
However, some of his earliest royal duties were in Wales, and he has maintained his links with the nation through engagements over his time as a working royal.
He has also been known as William Wales, particularly during his time in the armed forces, because of his father’s title.
Any decision to create William as Prince of Wales may take into account national mood and the work and base of William and his family at the time.
If he is the Prince of Wales, Catherine will be the Princess of Wales, a title which has not been used since William’s mother Diana was alive.
Camilla is technically the Princess of Wales, but has chosen not to use the title because of its association with the late Diana.
How much money will William make?
In the financial year 2019/20, the duchy made a “distributable surplus” of £22.3m. That’s the amount that goes to Charles, which he then uses for his work and for the Cambridges work.
That was an increase from the year before, but the total came before the impact of coronavirus was known.
It’s not clear how badly the duchy will be impacted, but William might inherit a portfolio that’s making a little less than that, depending on its recovery.
The assets of the duchy are currently valued at £909m. Commercial property on the duchy is about £295m.
Charles pays tax on the money he makes, something he does voluntarily, and William is likely to follow his lead on that. He pays the top rate of tax.
While Charles does meet lots of his expenses through the duchy money, there are some which are covered by the Sovereign Grant. For example, his travel abroad for royal tours will be paid by the grant, which is funded from the Crown Estate’s profits and not the Duchy of Cornwall.
Often, tours abroad are at the request of the UK government and help carry out soft diplomacy.
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