They’re masterpieces of Renaissance art but no one knows where they come from. Now, at last, one curator thinks she has an answer, writes Alastair Sooke.

Rome, 1604: Pietro Aldobrandini, an aristocratic Italian cardinal and patron of the arts, is hosting a grand meal at his private residence. Surveying the dining room, one of his guests, Fabio Masetti, ambassador to the Duke of Modena and Reggio, is impressed by the awe-inspiring collection of silver on display, glittering in the candlelight. The following day, Masetti writes to his boss, singling out a set of monumental silver objects that caught his eye: “I observed 12 [large serving dishes] with the 12 Caesars, and within sculpted all their triumphs and famous accomplishments, valued at 2,000 scudi.” 

There is a lot of beautiful Renaissance silver, but nothing quite like the Silver Caesars – Julia Siemon

His words describe the so-called 'Silver Caesars' – a set of 12 silver-gilt 'standing cups' that together comprise a stunning example of Renaissance silverware, arguably the most important suite of silver to have survived from the period. “There is a lot of beautiful Renaissance silver, but nothing quite like the Silver Caesars,” says Julia Siemon, curator of a spellbinding exhibition about them at Waddesdon Manor, the 19th-Century French-style chateau in Buckinghamshire, England, built by a member of the Rothschild banking dynasty whose father owned one. “Really, they are unique: there are no other Renaissance objects like them, no other complete suite.” 

Historically, the Silver Caesars have been known as the 'Aldobrandini Tazze', because they once belonged to Cardinal Pietro (1571-1621). A 'tazza' is a shallow, ornamental cup, mounted on a foot, which derives its shape from ancient drinking vessels; 'tazze' is the plural form. 

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Seeing the 12 tazze together in Waddesdon’s White Drawing Room – reunited for this exhibition for the first time in 150 years – is a magnificent sight. Each cup is around 16in (41cm) high and consists of a statuette of a Roman emperor standing in the centre of a dish decorated with four intricate scenes marking important moments from his life. Every dish in turn rests upon an ornate foot. 

There are 48 narrative scenes in total, each illustrating a specific passage from The Twelve Caesars, a famous literary work by the Roman historian Suetonius, written in the early Second Century AD, chronicling the lives of Julius Caesar and Rome’s first 11 emperors. 

These are artworks literally made of money – Siemon

On one dish, we see Julius Caesar with his cohorts, deciding to cross the river Rubicon; on another, Nero plays his lyre, while around him a conflagration engulfs Rome. 

You don’t need to know anything about Suetonius or Roman history, though, to be impressed by the phenomenal workmanship required to transform so much precious silver – the tazze have a combined weight of more than 82 pounds (5.85st). “These are artworks literally made of money,” Siemon says. 

The extraordinary thing about the Aldobrandini Tazze is that, despite being well-known to connoisseurs, little is known about their origins. Indeed, establishing the precise history of the Silver Caesars has eluded scholars for centuries. We cannot say for certain who they were made for, when they were fashioned, or why. 

Still, Siemon believes that she and her collaborators on the Waddesdon exhibition, The Silver Caesars: A Renaissance Mystery (which was first staged at New York’s Metropolitan Museum of Art last year), have found an elegant solution to the riddle of these impressive table ornaments, which were probably intended only for display, and never actually used for serving food. And following her sleuthing step by step makes for a fascinating art-historical detective story. 

Lock up the silver

In fairness, there are good reasons why confusion surrounds the Silver Caesars. Masetti’s letter is one of only a handful of documents that shed light upon their early history; unfortunately, none survives informing us of their original owner. Nor do any of the dishes conveniently carry a mark or guild stamp telling us where and when it was made. Moreover, the cups were designed in parts so they could be easily dismantled for storage or transportation; as a result, over the centuries, various elements were unscrewed, mixed up, sold off, and scattered. 

In 1826, all 12 tazze materialised, seemingly out of thin air, in England, when they were misattributed to the celebrated Florentine goldsmith Benvenuto Cellini. At some point during the 19th Century, the tazze were also gilded, while half had their original fluted feet and stems replaced with elaborate substitutes. 

By the 21st Century, the Aldobrandini Tazze were in museums and private collections all over the world (one sold at auction in 2013 for more than $1.4 million). In 2010, the classicist Mary Beard visited the Victoria and Albert Museum in London to inspect a supposedly intact tazza honouring Domitian – only to discover that, in fact, the dish depicted scenes from the life of Tiberius, ie another emperor altogether. 

Thanks to painstaking research by Beard and Siemon, all 48 vignettes have now been firmly identified – and, for the duration of the show, at least, each dish has been matched with the correct statuette. 

Simply assembling all 12 tazze in one place proved challenging enough. Yet Siemon is also proposing a hypothesis that may solve the “mystery” of the Silver Caesars. Her starting point, she says, was the little we do know about the tazze. Two recently discovered letters reveal that six of them were offered for sale in Milan in 1599. Siemon also notes that one visual source for the tazze dates from the late 1580s. Therefore, the cups were probably produced during the 1590s. 

None of the scenes looks like ancient Rome. In fact, they don’t look like Italy at all – Siemon

Then there is the broadly naturalistic style of their imagery, “chased” in relief, on the concave interior of the dishes, by craftsmen using various tiny steel tools, including tracers and punches. Early in their history, as we have seen, the tazze were in a collection in Italy – but stylistically they resemble silverware produced north of the Alps. Indeed, they were probably fashioned in the Low Countries. One giveaway is the distinctly Northern European appearance of buildings, including several half-timbered dwellings, which feature on several dishes. 

“None of the scenes looks like ancient Rome,” explains Siemon. “In fact, they don’t look like Italy at all. Ancient Rome, as shown on these objects, isn’t a time or a place, but an idea – an idea about imperial power. This is a Renaissance reinterpretation of ancient Rome.” 

During the 16th Century, the Low Countries were ruled by the imperial Habsburg dynasty – who, Siemon points out, liked to compare themselves with ancient Roman emperors. Intriguingly, given this context, the imagery on the dishes presents, in Siemon’s words, “a positive spin on imperial power”: mostly, we see military victories and triumphal processions, rather than any of the notorious passages from Suetonius concerning, say, the depraved sex lives of the Caesars. According to Siemon, the fact that the tazze celebrate imperial power so consistently suggests that they must have been intended for a Habsburg ruler, as a kind of flattering “mirror of princes”, instructing him how to rule. 

Siemon even has a specific ruler in mind: Archduke Albert VII of Austria, who governed the Southern Netherlands during the 1590s. Perhaps civic leaders in the Habsburg Netherlands commissioned the tazze as a gift for Albert, to curry favour with him. 

How, though, did the tazze get from the Low Countries to Italy, and Aldobrandini’s collection? Siemon has her answer ready: in 1598, Cardinal Pietro hosted Albert in Ferrara, northern Italy, as the latter celebrated his wedding to a Spanish princess. 

Siemon speculates that Albert gave several of the tazze to Aldobrandini as a kind of luxurious thank-you gift; Aldobrandini subsequently bought the rest so that, by the time of that dinner in Rome in 1604, he owned the complete set. 

It’s a compelling case. It also encourages us to shift attention away from questions of why and for whom the tazze were made, and onto the artistry of the cups themselves. 

For the Silver Caesars are more than a testament to the complex power networks spanning Renaissance Europe. First and foremost, they are spectacular works of art, full of delightful details that beguile the eye – making them, in the words of one contributor to the exhibition’s catalogue, “worth far more than their weight in silver”.

Alastair Sooke is The Telegraph’s Critic at Large

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