How to marry a monarch

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William’s approach to choosing his future queen had been both thoroughly modern and, by royal standards, deeply unconventional. Looking back over the long history of the British crown, few other heirs to the throne have been able to exercise such a degree of personal choice.

Calming troubled waters

One of the most important motivations in choosing a queen has been to ease tensions between rival nations. This was certainly the case with Henry V, who took the throne in 1413.

England and France had been battling it out in the Hundred Years’ War since 1337 and Henry was quick to take up arms. Having secured a triumphant victory at Agincourt in 1415, he concluded a treaty with the beleaguered Charles VI five years later. As well as recognising Henry as heir to the throne of France, it also provided for his marriage to Charles’s daughter, Catherine of Valois. The ink was barely dry on the treaty before the two kingdoms were at war again, but the marriage itself was a success because it gave Henry a son and heir, who took the throne as Henry VI at the age of just eight months upon his father’s untimely death in 1422. Catherine remained in England and later married a Welsh squire named Owen Tudor, thus spawning the royal dynasty of that name.

Hostilities between England and Scotland were also eased – temporarily at least – by a 16th-century marriage alliance. James IV of Scotland had first been asked to consider Margaret, eldest daughter of his English rival, Henry VII, in 1497. But James was having too much fun supporting the pretender Perkin Warbeck, who was threatening to unseat the first Tudor king. He changed his mind after Warbeck’s execution, and consented to take Princess Margaret as his bride as part of the so-called Treaty of Perpetual Peace in 1502, by which time she had reached the ripe old age of twelve.

As with the marriage of Henry V and Catherine of Valois, James and Margaret’s union endured for longer than the treaty. Their marriage also had a profound impact upon the history of the monarchy, for their granddaughter was the ill-fated Mary, Queen of Scots, and her son, James VI, became the first king of Scotland and England.

Boosting one’s legitimacy

Another powerful incentive to take a wife has been to bolster one’s legitimacy. Nobody was more eager to do so than William of Normandy – later known as William the Conqueror. He was probably only about seven years old when he inherited the duchy from his father. Worse still, he was illegitimate. Although he grew into a fierce warrior who saw off Normandy’s enemies and extended its territories, he never shook off the stain of bastardy. He therefore chose a wife with more than enough royal blood for both of them. Matilda was the daughter of William’s neighbours – Baldwin V, Count of Flanders, and his wife Adela of France. As such, she could trace her descent to most of the royal houses of Europe – including Alfred the Great.

Unfortunately, in Matilda’s eyes, William was punching well above his weight. When she heard of his proposal, she declared that she would not lower herself to marry a “base-born duke”. Furious, William rode over to Flanders and confronted his would-be bride, dragging her to the ground, rolling her in the mud and almost beating her to death “with his fists, heels, and spurs”. To everyone’s astonishment, just a few days later Matilda announced that she would marry none but William, since “he must be a man of great courage and high daring” to have ventured to “come and beat me in my own father’s palace”. They were betrothed shortly afterwards. Despite this inauspicious beginning, the marriage proved a resounding success, bolstering William’s claim not only to the duchy but to the throne of England, and producing no fewer than eight children.

Fast forward 400 or so years and another ruler was looking to strengthen his hold on power by taking a wife whose legitimacy was greater than his own. Henry Tudor might have vanquished Richard III at Bosworth in 1485, but his battle to hold onto the throne was only just beginning. The problem was, he was descended from an illegitimate line: his great-great grandparents were John of Gaunt (the third son of Edward III) and his long-standing mistress Katherine Swynford.

At the time of Henry VII’s accession, there were no fewer than 18 claimants with a superior right to the throne than his – including his prospective wife, Elizabeth of York, the firstborn child of Edward IV. Henry, a Lancastrian, hoped this marriage would win over his Yorkist rivals. He was right: the union of the warring houses – symbolised by the red and white Tudor rose – brought much-needed stability to the new dynasty. It also filled the royal nursery with heirs and spares.

Getting ahead of your rivals

The future Henry II had an eye to political and financial advancement when he chose Eleanor, duchess of Aquitaine, as his bride in 1152. Eleanor was one of the wealthiest and most powerful women in western Europe. As king and queen of England, their combined lands stretched from the Scottish border almost to the Mediterranean, and from the Somme in the north of France to the Pyrenees in the south. The icing on the cake was that Eleanor was a famed beauty and politically shrewd. As well as giving Henry eight children, she proved a highly able consort who wielded power on her husband’s behalf when he was off campaigning.

Another, more famous Henry also chose a wife for political gain. When Henry VIII decided to marry his fourth wife, Anne of Cleves, in 1539, he was desperately short of allies. His two greatest continental rivals, Charles V and Francis I, looked set to forge a new treaty. Like England, Cleves had rejected papal authority so it looked like a match made in heaven. Sadly, it proved anything but. Henry was famously revolted by his new bride when he saw her in the flesh for the first time. He was hardly an oil painting himself by then and Anne agreed to an annulment a little too eagerly.

Filling the royal nursery

Charles II, the ‘Merrie Monarch’, had already fathered numerous illegitimate children by his many mistresses by the time he restored the British monarchy in 1660. That was all well and good for a playboy prince in exile, but to secure his throne he needed a legitimate heir. He therefore chose Catherine of Braganza, a Portuguese princess whom he judged would fit the bill nicely. Although they developed a genuine affection for each other, Catherine was unable to bear a child with to give Charles. Upon his death the throne passed to his younger brother James – with disastrous consequences.

The eldest son and heir of George III was similarly devoted to his mistresses – one in particular. Maria Fitzherbert drove the future George IV to such fits of passion that it was rumoured he had secretly married her. Anxious for the succession, his father insisted that his wayward son take a suitable wife. Caroline of Brunswick, a German princess, brought the added bonus of wealth, which helped pay off some of her new husband’s colossal debts. They hated each other on sight but were married in April 1795 and conceived a child on their wedding night – their only conjugal encounter. A daughter, Charlotte, was born the following January and her parents separated two months later.

For love

Marrying for love is not a luxury traditionally afforded to kings and their heirs. But just occasionally, the heart has triumphed over the head. Take the popular Yorkist king, Edward IV, for example. Tall and handsome, he had a string of mistresses before becoming king in 1461.

Two years later, he caused a scandal of epic proportions that nearly cost him his throne. Apparently on a whim, he married the beautiful but impoverished widow Elizabeth Woodville – when he could have had his pick of Europe’s princesses. Although Elizabeth proved a fertile wife, her ambitious family caused divisions at the heart of the royal court and when Edward died suddenly in 1483, the kingdom was plunged into crisis. His two sons disappeared in the Tower of London shortly afterwards and his brother Richard seized power.

Anne Boleyn drove Henry VIII to such passion that he stopped at nothing to make her his wife

It's perhaps no surprise that Britain’s most-married monarch, Henry VIII, chose some of his wives for love. Anne Boleyn drove him to such passion that he stopped at nothing to make her his wife: separating England from Rome, making himself supreme head of a new Church of England and sparking widespread rebellion. But his ardour rapidly cooled when Anne failed to give him a son, and he had her executed on trumped up charges of adultery just three years after marrying her. Later, Anne’s cousin, Catherine Howard, caught Henry’s eye when she was just a teenager. Seeing her as an opportunity to recapture his lost youth, Henry fawned after her like a lovesick puppy. But this marriage would go the same way as his second: Catherine was condemned for adultery (justifiably this time) and sent to the block.

The most famous example of a king choosing to follow his heart rather than his head is Edward VIII. He was already head over heels in love with Wallis Simpson, an American divorcee, when he became king in January 1936. For a while, he laboured under the misapprehension that he would be able to marry her. But at the time, the Church of England forbade marriage to divorcees, and as head of that church the new king could hardly ignore the decree. By December that year, he had decided to give up the throne for “the woman I love”.

Many predicted that the abdication crisis would be the end of the monarchy. But Edward’s younger brother, known to the family as Bertie, took the reins as George VI, managed to steady the “rocking throne”, as he put it. Ever since then, royal heirs have been encouraged to put duty ahead of love when it comes to choosing a wife – with mixed results.

Tracy Borman is a royal historian. Her books include Crown & Sceptre: A New History of the British Monarchy from William the Conqueror to Charles III (Hodder & Stoughton, 2022)