Marguerite Louise of Orléans was born in July 1645 to Gaston, Duke of Orléans and his second wife Marguerite of Lorraine. Her father was the brother of King Louis XIII of France, making Marguerite the granddaughter, niece and cousin of three French kings. Marguerite’s older half-sister was La Grande Mademoiselle; a high ranking heiress at the court of their cousin King Louis XIV of France.

Marguerite spent much of her childhood away from the main French court because her father was frequently caught up in plots against the ministerial governments of the crown. In 1652 Gaston was exiled to his own court at Blois after taking part in an uprising known as the Fronde des nobles, part of the ongoing civil war. Gaston had reconciled with Louis XIV by 1656, but this tumultuous early life meant that Marguerite received only a basic education for a woman of her rank and was known to be an unruly child.

In 1658, Marguerite received a marriage proposal from Cosimo de’ Medici, Grand Prince of Tuscany. The teen seemed excited about the idea of marriage at first but then started acting irrationally and purposefully going against her royal duties. Marguerite became the lover of her cousin Prince Charles of Lorraine and often went out with him unaccompanied and without permission.

On 19 April 1661, Marguerite and Cosimo were married by proxy; but when she was due to meet with diplomats after the ceremony, Marguerite attempted to run away to go hunting, only to be discovered and returned by her older sister. After this, Marguerite made her journey to Tuscany; firstly in a magnificent fleet of 18 ships and then by travelling very slowly over land. She often took diversions and long breaks along the way and delayed many of the pageants which were put on for her progress. The Princess finally entered Florence on 20 June and took part in her wedding celebrations which were the most spectacular ever seen in Florence.

Cosimo and Marguerite’s marriage was a disaster from the start; the pair greeted each other with no enthusiasm and would not sleep together regularly, endangering the future of the dynasty. Nonetheless, the couple went on to have three children together; a daughter named Anna Maria Luisa and two sons named Ferdinando and Gian Gastone. Marguerite was closest to her eldest son Ferdinando and supervised his education.

Marguerite was bored with life in Florence and unhappy without her true love Charles of Lorraine, and she quickly became a thorn in the side for her new family. Within days of marrying Cosimo, she had demanded that he hand over the crown jewels to her and when he announced that he could not do so, Marguerite proceeded to steal some of them and attempted to smuggle them out of Florence. Her spending habits were extreme, and she refused to cut her outgoings even when her father in law, the Grand Duke intervened. When she was not locking herself in her rooms and refusing to eat altogether, Marguerite would arrange lavish banquets for every meal, which cost ten times what Cosimo was spending on food. The people of Florence were angered by Marguerite’s excessive spending and the lack of respect shown to her Medici family.

Marguerite’s dislike for Cosimo steadily became utter hatred. She pleaded endlessly in letters to the French court to be allowed to return to her native France but was not allowed. Marguerite often stayed away from Cosimo at other properties owned by the family, where she maintained her own French retinue as she refused to mix with the locals or learn the Italian language at all. Marguerite was known to be engaged in various affairs during this time period, but after a visit from her lover and cousin Charles of Lorraine, Cosimo began to take more notice. He had his wife’s mail checked and wrote to Louis XIV in the hope that he could bring his cousin’s behaviour into check. As there was nothing Louis could do, Cosimo instead removed all of Marguerite’s French staff and friends.

From then on, Marguerite went out of her way to mock and embarrass Cosimo at any given opportunity. She would refuse to eat the food prepared by Italian cooks as she said the Medici were trying to poison her and she would often tease Cosimo in public. In 1664 Marguerite refused to return from Palazzo Pitti; fearing that she would run away, Cosimo imprisoned his wife in the Villa de Lappeggi where she was under the guard of 40 soldiers.

In 1570, Cosimo’s father died, and he became the Grand Duke of Tuscany. Marguerite had been briefly reconciled with her husband at this time and hoped her new role as Grand Duchess would give her more power. She desperately sought out political roles for herself and fought with her mother in law Vittoria over precedence. Despite her wishes, Cosimo refused to allow Marguerite to join his Consulta (similar to the English Privy Council) but granted his mother a place instead, this was the final straw for Marguerite and after the birth of the couple’s final child Gian Gastone, the pair were bickering endlessly. If Marguerite was not rowing with Cosimo or threatening to smash bottles over his head if he came to her room again, she was fighting with her mother-in-law instead. It was said at the time that “The Pitti Palace has become the devil’s own abode…only the noise of wrangling and abuse can be heard”.

Marguerite became determined in her mission to return to France at any cost. She told Louis XIV that she believed she was suffering from breast cancer and wanted to be treated in France. This plan backfired as Louis sent his own doctors to assist his cousin and found there were no signs of the illness. After her plans continued to fail, the Grand Duchess asked to be allowed to visit a shrine in Prato where she stayed at a Medici villa. She refused to go back to Cosimo for two whole years and pleaded with him in letters to be allowed to return to France. She wrote with utter desperation ‘you make the unhappiness of my life and I make the unhappiness of yours’. After 13 difficult years of marriage, Cosimo finally agreed to a separation.

Cosimo reached an agreement with Louis XIV that Marguerite could return to France as long as she settled in a convent in Montmartre and gave up the rank of Princess of France. Cosimo provided the wife that despised him with a yearly pension, paid off all of her debts and released her from her unhappy marriage. After a few months of piety and solitude at Montmartre, it seemed that Marguerite had finally settled down into religious life and as a patron of a number of charities. This was not to last; however, as Louis XIV did not force her to stay at the convent as he had agreed with Cosimo. Marguerite visited the French court often; spending her time dressing in expensive clothes and heavy makeup, taking numerous lovers and gambling her pension away.

Even in France, released from her marriage to Cosimo, Marguerite continued to bring misery to his life; she would send him long abusive letters for no reason other than to hurt him. In one letter she said ‘no hour of the day passes where I do not desire your death and wish to see you hanged’ and went on to say that even when they die they would both undoubtedly go to hell and that her only problem with that was that she would have to see him there.

Cosimo continued to keep a close watch over his estranged wife’s behaviour at the French court, through the reports of envoys. He tried on numerous occasions to gain explanations for her scandalous liaisons and behaviour, before eventually giving up with trying to control her conduct. It is likely that Cosimo was negatively impacted by Marguerite’s actions at the French court, by rumours back in Florence and this is why he tried to stop her embarrassing behaviour, rather than out of any genuine fondness for her. Their final dealing with each other came when Cosimo was required to consent to Marguerite’s move to another convent; after she threatened to kill the Abbess in charge of Montmartre, with rumours also circulating that she had also tried to burn the Abbey down.

In the early 1700s, Marguerite finally began to change her ways in her old age. She moved into Saint-Mandé Abbey and led a quiet life, even reforming the convent which had always had a bad reputation. Marguerite’s health began to decline from 1712 onwards, and she had frequent attacks of apoplexy. Marguerite briefly lost the ability to speak after one of her attacks and also lost the use of her left arm. She lived out the remainder of her days in a modest house in Paris which she had purchased for herself and died in 1721 at the age of 76. Her children were the last of the great Medici dynasty as they all died, leaving no heirs to continue the family.