There are 14 active monarchies across Europe, ranging from the obvious to the more obscure.
Some are hugely independently wealthy, some receive generous grants and upkeep costs from their governments and some receive nothing at all.
There's even a billionaire prince who doesn't have a country.
Keep scrolling for the complete list of European royals, ranked by what they receive from the states they preside over.
Albert, Prince of Thurn und Taxis — no salary nor country
Albert, Prince of Thurn und Taxis, does not have a country to rule over, but is technically a German prince. After the death of his father in 1990 he became one of the world's youngest billionaires, and his assets include real estate, art and a tech company.
In 2014, Forbes estimated his wealth to be about $1.6 billion (£1.23 billion).
The Pope, Vatican City — no salary
The Pope, the head of the Catholic Church, does not get paid an annual salary. However, he is in charge of the Vatican budget, which has revenues around $300 million (£230 million) per year, which goes towards covering his expenses, among other things.
The Vatican's wealth has been estimated to be somewhere in the region of $10 — $15 billion (£7.7 — £11.5 billion), which includes shareholdings and investments.
Source: Time Magazine
Giacomo dalla Torre del Tempio di Sanguinetto, Grand Master of Malta — no salary
British Queen Elizabeth II was the official Queen of Malta until 1974, when the country became a republic. However, there is a Grand Master of the Knights of Malta — the head of a Catholic fraternity founded in 1048. The Order has no territory, but is considered a sovereign entity and prints its own postage stamps and coins.
The Grand Master governs as the Order's sovereign and religious superior. He is not given a salary, but his living costs are met.
The Order has benefactors, both private citizens and public organisations, that make donations to support its charitable work.
Source: Sovereign Order of Malta
Co-princes Joan Enric Vives Sicilia & Emmanuel Macron, Andorra — unknown
Andorra has two co-princes, one who is appointed by the Pope and the other who obtains the position by dint of becoming the French president — currently Emmanuel Macron.
They have various powers independent of the government, such as to pardon, although most of their roles require governmental approval.
Before the 1993 constitution, Andorra paid a tribute of approximately $460 (£353) to the French ruler on odd-numbered years, and a tribute of approximately $12 (£9) to the Spanish bishop, plus six hams, six cheeses, and six live chickens on even-numbered years.
Now, the General Budget of the Principality assigns an equal amount of money to each prince for carrying out their duties, which can be refused. The amount is not noted, but it is likely to be small: in 2016 the head of the Andorran government was paid roughly €71,000 (£63,000) per year.
Source: All Andorra
Prince Hans-Adam II, Liechtenstein — small allowance
The Prince does not receive a salary, but accepts a token expense allowance of 250,000 Swiss francs (£200,000) and pays no taxes.
The Princely House of Liechtenstein gets its wealth from its privately owned bank, LGT Group, and extensive investments made through the Prince of Liechtenstein Foundation, which looks after assets including real estate, a forest and a winery.
In 2008, Forbes estimated the family had a net worth of roughly $5 billion (£3.8 billion).
Source: Forbes, Western Europe 2014 (Wayne C. Thompson)
King Felipe VI and Queen Letizia, Spain — £7m
The Spanish crown receives a lump sum of money from the state, which amounted to €7.8 million (£7 million) in 2014 and 2015.
Of this, the King received an allowance, paid in monthly installments, of €236,544 (£211,124). The Queen received, €130,092 (£116,112), the Prince €189,228 (£168,892) and the Princess €106,452 (£95,012).
Spain's National Heritage group manages the country's eight royal palaces, five royal county residences and ten monasteries and convents founded by the crown. Many house art collections are open to the public, but they are also at the disposal of the royal family.
Grand Duke Henri, Luxembourg — £9m in running costs & a small allowance
Although they do not receive a salary, the Grand Ducal Family of Luxembourg has been granted 300,000 gold francs (£240,000) every year since the constitutional revision of 1948, to carry out its functions.
The 2017 budget also allows for €10.1 million (£9 million) for the Grand Duke's household costs.
The ownership, administration, control and income of the private fortune of the Grand Duke's House belong exclusively to the holder of the crown.
Queen Margrethe II, Denmark — £9.6m
As of 1 April 2017, the Danish Civil List grants the royal family £800,813, a month, or £9.6 million for the year. Prince Henrik, the husband of Queen Margrethe, gets 10% of this, while Princess Benedikte, the Queen's sister, gets 1.5%
The money covers the cost of the Queen's activities and the royal household's operations as well as some more private expenses.
The royal art collections belong to the Queen in her capacity as sovereign and a private person, although large parts of the collections are on show in galleries and museums for the public to see. Some of the royal palaces are privately owned by the royal family, while some are the property of the state.
King Philippe, Belgium — £10.4m
Belgium's Civil List covers all expenditure directly incurred by the King, and was set at €11.6 million (£10.4 million) annually in 2013. A number of additional support services are also financed by the government on top of that.
Belgian royal properties are owned either by the State or by The Royal Trust. The Trust properties can never be sold, some must retain their function and original appearance and be at the disposal of the royal family.
Some are used by the royal family while some are public parks, golf clubs and buildings open to the public. The Trust is an autonomous public institution and is financially independent.
King Carl XVI Gustaf, Sweden — £11.8m
The Swedish crown was allocated roughly £6 million in 2015 by the state to cover the cost of the King's official duties and the royal household's expenses.
Separately, the Palace Administration, which looks after the palaces and the royal art collections, was allocated £5.8 million, but also generates revenue from visitors to the palaces.
The family's private finances include Solliden Palace, which is open to the public, and Stenhammer, which they lease from the state.
Earlier this year, Royal Central reported that the King's personal fortune is about £54 million.
King Harald V, Norway — £25.8m
In 2017, the Norwegian government allocated £23.8 million to the royal house, to be distributed between the royals, and an additional £1.1 million in an grant for the King and Queen to cover personal expenses, and £900,000 for the Crown Prince and Princess.
The royal household ended the 2016 financial year with a surplus of about £630,000, although the Crown Prince and Princess ran a deficit of about £140,000.
The Royal Residences are owned by the state and are open to the public, but are at the disposal of the royal family. The King owns the royal yacht, although it is manned and maintained by the Royal Norwegian Navy.
King Willem-Alexander, Netherlands — £35.8m
In 2015 the budget for the King of the Netherlands was €40.1 million (£35.8 million) which included money for his wife and the former Queen, who abdicated after reigning for 33 years. From January 2014, the King's budget no longer covered the cost of private flights.
His personal allowance covers the costs of official visits and overseas tours, but the King also has a personal fortune, made up of real estate, investments and a stake in Shell Oil.
In 2007, Forbes estimated the former Queen's wealth to be around $300 million (£230 million).
Prince Albert II, Monaco — £39m
In 2015, the amount Monaco spent on the royals was €43.5 million (£39 million), up from €35.7 million (£32 million) in 2013 — although this is not broken down into salary or running costs.
Forbes estimated that the House of Grimaldi, Monaco's royal family, were worth $1 billion in 2010. This is made up of land and palaces, as well as art, antique cars, shares in the Societe des Bains de Mer resort and a rare stamp collection.
Prince Albert II, the reigning monarch, is one of the richest in the world. In 2006 he established the Prince Albert II of Monaco Foundation, which supports sustainable and ethical projects around the world.
Queen Elizabeth II, UK — £42.8m
In 2016-17, the Sovereign Grant, which is calculated as a percentage of Crown Estate profits, was £42.8 million. The Queen also received £14.9 million generated from sources including property rental.
"In 2016-17 the Sovereign Grant equated to a cost of 65p per person in the United Kingdom – the price of a first-class stamp," said Sir Alan Reid, the keeper of the privy purse.
The Crown Estate, which includes Buckingham Palace and the crown jewels, is not considered the Queen's personal property, but belongs to the British state. However, the Queen does own her residences at Balmoral Castle and Sandringham Palace.
In 2011, Forbes estimated the British royal family's net worth to be $500 million (£383 million), made up of property, art, and investments.
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