“They were on a level with today’s billionaires” – your guide to the Medici: bankers to the Pope, rulers of Florence, patrons of the Renaissance

Cosimo's father, Giovanni, had made his money from the wool trade and banking. At the crossroads of the Mediterranean, linking the Silk Roads to the east with the routes to northern Europe, Italy was one of the wealthiest parts of the continent. The Medici were bankers to the popes, a lucrative business, and in their home city they built an alliance with a group of prominent families (often cemented by marriages) that gave them control of the city authorities.

• Listen | Historian Catherine Fletcher responds to listener questions about the Medicis, from their role in the Renaissance to stories of dark deeds and scandalous affairs

Masters of Florence

Florence was not a democracy in the modern sense, but its ruling councils were elected by a limited male elite. Wives could and did exercise informal influence, although they were expected to maintain a demure public profile.

The Medici did not always get their way. In 1433, opponents contrived to have Cosimo arrested, but as banker to the Republic of Venice and the duke of Ferrara he had influential friends. He evaded execution and was exiled instead, albeit not for long; when his supporters won elections the following year, Cosimo returned to power. He used his wealth to patronise art, architecture and cultural projects, commissioning a new palace for the family, bronze sculptures by Donatello and enabling the completion of the dome for the city's cathedral to the design of Filippo Brunelleschi.

After Cosimo's death in 1464, his son Piero de’ Medici (Piero the Gouty) became head of the family. He survived an attempted coup but died in 1469, leaving his 20-year-old son Lorenzo de’ Medici in charge. This Lorenzo came to be known as 'the Magnificent', although his own rule was not without serious challenges.

A second Piero succeeded in 1492. He proved a weaker ruler. In 1494, when war broke out on the Italian peninsula and French troops marched south to assert an old claim to Naples, the Medici were once again expelled from Florence, gaining Piero his nickname: 'the Unfortunate'. The family were left dependent on their power base in Rome, where during 18 years of exile Piero's brother, Cardinal Giovanni de' Medici, rebuilt alliances.

In 1512, the Medici finally retook Florence with the help of the Spanish. This was not a pretty business. Their troops sacked the nearby town of Prato, torturing, raping, and murdering not only rival soldiers but women, children, and priests, “without the slightest pity”. Fearing the same treatment, the Florentines surrendered.

In 1513, Cardinal Giovanni was elected Pope, taking the name Leo X. He was an important patron of the arts. Raphael painted a triple portrait of Pope Leo with his cousin Cardinal Giulio de' Medici and another relative, Luigi de’ Rossi. Leo commissioned Michelangelo to design a funerary chapel for the family. It was needed.

The next years were far from easy. The Medici lost two heirs in quick succession: first Leo's brother Giuliano, then his nephew Lorenzo. Leo moved quickly to shore up his power in Rome, but no quantity of manoeuvring in the papal court could solve the problem that the Medici faced in 1519: they had no legitimate male heir in the main line, only two illegitimate boys – Ippolito and Alessandro, both under ten – and an infant girl called Catherine, who was excluded from the political structures of the Florentine Republic due to her sex.

The Medici dukes of Florence

Ippolito, the son of a gentlewoman, was legitimised and promoted as a future ruler. But after the Medici were exiled again in 1527, Ippolito’s uncle Pope Clement VII (Leo's cousin Giulio de' Medici) opted to make him a cardinal. This meant that when the Medici regained power (again with Spanish backing) it was Alessandro who became first ruler of the city and then in 1532 duke of Florence: the first of the Medici to hold that title.

Alessandro – whose mother was described as “a slave” and “half-Negro” (she had probably worked in the Medici household) – was widely regarded as unsuitable to rule, but he succeeded in winning the favour of the Holy Roman Emperor (and king of Spain) Charles V, whose daughter Margaret he married in 1536.

This alliance with the emperor had an impact, too, on Henry VIII's 'Great Matter' – his attempts to secure a divorce from his first wife, Catherine of Aragon. Pope Clement was reluctant to alienate his key ally by insisting that Catherine, who was Charles V's aunt, agree to a divorce.

In 1537, Alessandro was assassinated by a distant cousin, Lorenzino, who claimed he wanted to restore a republic; that, however, did not happen). Instead, another cousin, Cosimo, became duke of Florence. Over the course of a 37-year reign, Duke Cosimo built on Alessandro's achievements. He conquered Siena, and was granted the title Grand Duke of Tuscany. Alessandro's half-sister, Catherine de’ Medici, went on to be the first of two Medici queens of France.

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Like his predecessors, Cosimo ran a spectacular, cultured court. Italian mannerist Bronzino's portraits are testament to the glamour of the Florentine ruling family, while in the Palazzo Vecchio under the supervision of Giorgio Vasari, a series of frescoed rooms glorified the history of the Medici. Cosimo’s successors likewise played host to a range of leading artists and thinkers, including Galileo Galilei, whom his son Ferdinando (so far as he could) protected from the Inquisition, as well as Artemisia Gentileschi, who during the reign of Cosimo II became the first woman to join the Florentine Academy.

The Medici queens

Meanwhile, in France, Catherine de' Medici had become the single most powerful member of her line. She was married in 1533 to Henry, Duke of Orléans, the second son of the French king Francis II. When Francis’s heir died unexpectedly, Henry stood to inherit the crown – which he did in 1547, as Henry II, with Catherine becoming queen consort. When Henry died in 1559 following a jousting accident, she became a key adviser to her sons.

Her Medici background was not an asset: she was attacked for her mercantile origins and ‘Machiavellian’ courtiers. She was blamed for the St Bartholomew's Day Massacre of 1572, in which leading Huguenots (Protestants) were killed, and which prompted a wave of religious violence across France. Still, she was not the only Medici queen of France: Marie de' Medici, wife of Henry IV, also held that title, and ruled the kingdom as regent following her husband's assassination.

The Medici grand dukes of the 17th century continued with the patronage of arts and sciences established by their forebears, but as Europe's economic centre of gravity shifted towards its Atlantic ports they became relatively less influential. The main line of the dynasty ended in 1737 with the death of Gian Gastone. His sister Anna Maria Luisa left the family art collection to Florence, ensuring it stayed intact while other great collections were split up and sold off.

Medici Q&A: 9 huge questions about the famous family, answered

Why are the Medici famous?

The Medici are famous as the ruling family of Florence from the 15th century through until early in the 18th. They made their money as bankers, and became extremely wealthy patrons of the arts. Gradually they shifted from having a leading role within the city government to become the hereditary dukes of the city state of Florence, and then the Grand Dukes of Tuscany.

How did the Medici make their money?

The Medici made their money in the wool trade and banking. They imported wool from northern Europe – including from England and the Low Countries – to Florence, where they processed it into a very refined cloth. Alongside that trade, the Medici were bankers: they lent money to other people and hoped to get a large return on what they had lent out. This mercantile background wasn't always helpful to their reputation, because a lot of people were quite snobbish about merchants; trade was not an aristocratic thing to do.

How rich were the Medici?

They were on a level with today's billionaires – that's the kind of scale that we're looking at. When Giovanni di Bicci de’ Medici died in 1429, he left an estimated fortune of 180,000 gold florins. He wasn’t the richest man in Florence, but he was getting there. The family very quickly become one of the richest in Europe.

When and why did the Medici bank decline?

The Medici bank operated at a time when there are no national banks, so it was lending money to other states and governments.

One their clients was Edward IV of England during the Wars of the Roses. He was a bad risk, but because he was a king, they couldn't turn him down, particularly because he was also the person who had to agree to their wool exports. Edward didn't pay back his loans directly. Instead he gave the Medici’s a reduction in their wool tariffs, but this wasn't the same as actually having cash.

By this point, the Medici bank had branches all over Europe, and a number of other factors came into play, including mismanagement at the branch in Bruges and wider economic problems. As such, over the course of the 15th century the Medici became much more dependent on holding offices within the city of Florence – and the patronage possibilities this provided – rather than making their money privately as merchants.

How many Medici popes were there?

There were two major Medici popes in the early 1500s: Pope Leo X (Giovanni de’ Medici), who was elected in 1513, and his cousin Clement VII (Guilio de’ Medici), who was in power from 1523–34.

Later on in the century there were a couple more. One was Pius IV, who was from a very distant branch of the Medici family in Milan rather than the main Florentine ruling family. Then there was Leo XI, a much closer relative, but he lasted less than a month as pope before he died.

How important were the Medici to the Renaissance?

Being magnificent was regarded as a princely virtue, and the ruling families in all the Italian states at this time competed in magnificence via their patronage. This was very much part of showing off their honour, as well as the honour of their state. If a family had aspirations towards nobility, then they would want to host the best festivals, to patronise the best artists and so on. For the Medici that included artists like Leonardo da Vinci, Sandro Botticelli and Michelangelo Buonarroti, and later Artemisia Gentileschi, and scientists like Galileo.

Patronage also meant doing good works for your church. For a family like the Medici – who were involved in a certain amount of dubious political business as well as moneylending, which was still regarded as quite problematic for Christians – endowing your local chapel with gorgeous religious art and educating people who weren't literate about the stories of the Bible was one way of atoning for your sins.

Were the Medici corrupt?

In the 15th century the Medici absolutely had their hands in the till in terms of the Florentine state. Before they were officially the hereditary rulers of the city, they were borrowing money from the government to fund their own lifestyle.

Over decades the Medici gradually took over the state. Along with allied families, they increasingly manipulated the governing structures by setting up emergency committees and then policing who could be elected to them. They began to appropriate more and more state power for themselves.

Were the Medici as bad as the Borgias – or did they benefit from better PR?

It’s quite difficult to draw a line. Where the Medici had an advantage over the Borgias is that they weren't foreign; the Borgias were somewhat stigmatised on the basis of being from Spain. In turn, Spain was stigmatised as being home to a lot of Jews and Muslims, and the Borgias were alleged to be too favourable to Jewish people. The Borgias also failed to establish themselves in a state, whereas the Medici succeeded – despite making themselves quite unpopular along the way.

More successful than either of them were the Farnese, who came to power much more discreetly and made themselves Dukes of Parma and Piacenza. We don’t talk about them much now: they’re not as famous because they never became embroiled in controversy in the same way the Borgias or Medici did.

What happened to the Medici? Do the Medici still exist?

The Medici continued to rule in Florence until they ran out of legitimate heirs in the main two lines of the family. At that point, in 1737, a junior line of the family tried to make a claim, but they weren't regarded as legitimate enough to take over. This branch of the Medicis still exists today.

Catherine Fletcher is a historian of Renaissance and early modern Europe. Her latest book is The Beauty and the Terror: An Alternative History of the Italian Renaissance (Bodley Head, 2020).

This content was first published by HistoryExtra in 2021