IfQueen Elizabethdoes decide toretire at 95and appointsPrince Charlesas regent, she won’t be the first to do so.

In fact, the idea of installing a regent — effectively naming someone to wield the powers of government while the monarch is unable — is as old as the royal family itself.

Queen Elizabeth II and Prince Charles, Prince of Wales

While the modern process is lengthy, complicated and involves everyone from family members to senior courtiers and civil servants, it has historically provided an easy way for the British government to continue working should the monarch fall ill, go mad or set out on an overseas war (generally against the French).

Today, however, “The Queen can’t just wave a queen wand and say, ‘Charles, you are my regent.’ It’s not her call – and it’s not his call,” says Sally Bedell Smith, a veteran biographer of both the Queen and Charles.

Here are five examples of monarchs who have trod where Elizabeth my soon venture — with varying degrees of success.

George III (left) and George IV.Universal History Archive/UIG/Shutterstock (2)

George III George IV

Monarch: George IIIRegent: George IV

George Augustus Frederick, Prince of Wales, was appointed Prince Regent in 1811 after his father, King George III — the man who lost America — slipped into insanity (partly as a result of the disease porphyria).

An excessive drinker, gambler and womanizer,Prince Georgespent a vast chunk of the royal finances on paintings, clothing, over-the-top parties and palace-building. He also secretly married Maria Fitzherbert in 1785, only to later tie the knot with Princess Caroline of Brunswick in 1795 to pay off his debts.

By the timePrince Georgebecame regent, he was already a national joke and hugely disliked for his mindless excess. This continued throughout his regency, which lasted until his father died in 1820, after which he was crowned George IV.

Queen Catherine of Aragon (left), Henry VIII, Catherine Parr.Universal History Archive/UIG/Shutterstock (3)

Queen Catherine of Aragon Henry VIII Catherine Parr

Monarch: Henry VIIIRegent: Catherine of Aragon & Catherine ParrHenry VIII famously had six wives. Less famously, two of them also ruled as regents while the Tudor monarch was away fighting the French.

Around 31 years – and five wives – later, Henry’s last spouse Catherine Parr also served as regent between July and September 1544, while the King again crossed swords with the French. Although Catherine didn’t have to organize a war against the Scots, Tudor sources describe her as studiously attending to government affairs. She also developed close bonds with Henry’s children Mary, Edward and Elizabeth.

Richard I (left) and William Longchamp.Historia/Shutterstock (2)

Richard I William Longchamp Bishop of Ely

Monarch: Richard IRegent: William LongchampWhen Richard the Lionheart set off on the Third Crusade in 1190, he had a choice of regents to look after England: his scheming, treacherous, troublemaking brother, John (later King John); or trusted, efficient and loyal courtier William Longchamp.

It wasn’t much of a decision. It also didn’t much go to plan.

While Longchamp was fiercely loyal to Richard, he wasn’t exactly brilliant at making himself popular among the people, who regarded him as arrogant, pompous and cruel — mainly because he was French and massively anti-English.

In 1191, John used this festering resentment to lead a rebellion against Longchamp, forcing him to flee to France. With Richard also jailed in an Austrian prison, John effectively installed himself as King (cue Robin Hood).

Yet Longchamp had the last laugh. In March 1194, Richard I returned to England and collapsed John’s rebellion pretty much overnight. Longchamp was then handed control of the royal finances as Chancellor of the Exchequer.

As King, John would go on to surrender his royal lands in France, lose his priceless crown jewels in a Norfolk bog (never found) and sign away a vast chunk of his royal powers to rebel barons in the Magna Carta.

William and Mary.Michael Nicholson/Corbis via Getty

Engraving of William & Mary (King William and Queen Mary)

Monarch: William III & Mary IIRegent: Mary IIOn April 11, 1689, Mary — eldest daughter of beheaded King Charles I — was crowned alongside her husband William of Orange at Westminster Abbey. Yet this was no normal coronation: The pair had effectively been sailed in from Holland to shore up the protestant nature of the English crown, in what was known as The Glorious Revolution.

More crucially, Mary was also crowned “queen regnant” as opposed to queen consort, which meant that she and William ruled as dual sovereigns.

This was enshrined in law through the Regency Act of May 1690, which confirmed “the Queen’s Majesty to exercise and administer the regal power and government of the kingdom” while William was fighting in Ireland.

Mary used her power to discourage drinking and help the poor. She also established the naval hospital in Greenwich and sternly punished anyone who even remotely thought of plotting against her and William.

Such was her influence that the period in history and its French-influenced architecture is now referred to as “William and Mary” (as is the second oldest higher education institution in the U.S.).

George II and Caroline of Ansbach.Historia/Shutterstock (2)

George II King of England Caroline of Ansbach

Monarch: George IIRegent: Caroline of AnsbachCaroline of Ansbach served as regent four times during the reign of husband George II, who assumed the throne in 1727.

When she died in agony following bowel surgery in 1737, Queen Caroline — the first Princess of Wales since Henry VIII’s first wife Catherine of Aragon — was deeply mourned across Britain. Despite straying countless times during their marriage, George II was so heartbroken he never married again. When he died, 23 years later, the King asked to be buried next to Caroline and to have the sides of their coffins removed, so that their dust could mingle together forever.

source: people.com