Sienese sculptors and painters were among the very first in Europe to break free of the symbol-heavy, repetitive aesthetic conventions of the Dark Ages and restore some sense of illusion and individual life to the visual arts. They managed to achieve this without losing sight of the ultimate purpose of their work, which was to enable contemplation and prayer and to glorify God. 
How precisely the Sienese might have been influenced by the rediscovery of Roman sculptures or the revival of particular Latin texts is not entirely clear. We should also ask ourselves how far the Sienese really needed to immerse themselves in the classical tradition to accomplish what they did. It might be more important to investigate the spiritual and theological roots of these artists’ approach to reality. Siena: The Rise of Painting 1300–1350 seems an ideal place to begin. Those of us who missed the exhibition at the Metropolitan Museum of Art in New York from October to January and at the National Gallery in London this spring still have access to an excellent catalogue with high-quality illustrations and some unusually illuminating essays. The curators of this exhibition have enabled nothing less than a revival of sacred art. 
The exhibition focuses largely on Duccio di Buoninsegna, who is too little celebrated except among connoisseurs. Perhaps this is because only two altarpieces are explicitly documented as his work. Then again, these are two of the most ambitious large-scale achievements not just of early Sienese painting but of all art before the Renaissance. We have no excuse not to sing Duccio’s praises.
The first known painting by Duccio is the Rucellai Madonna, which now hangs in the Uffizi Gallery in Florence, alongside Cimabue’s Santa Trinità Madonna and the Ognissanti Madonna by Cimabue’s greatest pupil, Giotto. Giorgio Vasari, the pioneering biographer of Renaissance artists, mistakenly attributed the Rucellai Madonna to Cimabue, but in 1790, a contract for the commission of this altarpiece dated April 15, 1285, was discovered. It took art historians a century or so to begin correcting this attribution. 
The Rucellai Madonna is around eleven by fifteen feet, painted in egg tempera in the Byzantine style, with a gold-leaf background. Our Lady and her Son are disproportionately larger than the six angels who surround their throne. Baby Jesus looks like a little man, and makes a familiar blessing gesture with two outstretched fingers of his right hand. The stylistic conventions of the altarpiece are recognizably Byzantine, albeit with little touches here and there that we might characterize as Gothic: the tapering fingers on the hands, for example, and the attempt at realistic-looking light and shadow as seen on folds of drapery. 
It is very hard to distinguish this picture from documented work by Cimabue. Say what you will about Vasari’s own paintings, but you cannot deny that he knew a great deal about art and had an eye that few connoisseurs could match. This panel does not look revolutionary to us, but according to Vasari, to its original viewers it seemed astonishingly realistic in its rendering of flesh, its natural-looking poses, and the way the artist relied on the observation of reality to create the image, rather than repetitive patterning in the Byzantine manner.
Byzantine stylization has its advantages. It requires a lower level of technical competence on the part of the artist, so there is scope for production on a large scale. On the other hand, Byzantine art is so conventional by nature that it leaves no room for individual genius. A Byzantine work of art stands out from others in its milieu only in terms of the costliness of its materials. No real greatness is possible within these conventions, not, at least, by Renaissance standards. This is not to say that beauty is impossible in the Byzantine tradition. But for Byzantine artists the tradition itself does all the work. There can be no individual fingerprint, as there is in the classical tradition, where dozens of Greek vase painters whose names are permanently lost to us can still be identified based on their handiwork. 
How Sienese art developed or rediscovered the classical sense of individual personality is difficult to reconstruct with any confidence. We could easily imagine a process that aligns conveniently with our own prejudices, but in truth all we know is that between the mid-thirteenth and mid-fourteenth centuries, Siena became perhaps the most important center for artistic innovation in Italy—which is to say, the world. 
In the Middle Ages, many Sienese believed themselves to be descended partly from Remus, the murdered brother of Romulus, the legendary founder of Rome. According to this story, the city was founded by Remus’s son Senius, after whom the city was named, and his brother Aschius, who gave his own name to Asciano, which is twenty miles from Siena and was not part of Sienese territory until the late thirteenth century. This set of legends sounds suspiciously medieval in origin, let it be said. Another tradition holds that the Sienese are descended from the Senonii, who besieged Rome and helped sack it in 390 B.C. This is equally implausible, but it has a more respectable literary basis in Livy’s history of Rome.
Siena’s patron saints were originally Saint Ansanus, “the Apostle of Siena” (martyred in A.D. 304), Saint Sabinus of Spoleto (a bishop martyred in 303), Saint Crescentius of Rome (martyred in 303, aged eleven), and Saint Victor (a soldier whose precise martyrdom date is disputed). Their veneration was eventually overshadowed by devotion to the Franciscan missionary Saint Bernardino da Siena (1380–1444) and Saint Catherine of Siena (1347–1380). But the most constant patron of the Sienese was always the Virgin Mary.
On September 3, 1260, the people of Siena vowed to dedicate the city to Our Lady if they were victorious in battle against the Florentines. The next day, they defeated the enemy at Montaperti, just outside Asciano. In the wake of their victory they found themselves Ghibellines, allied with the Holy Roman Emperor. Florence was Guelph, allied with the pope. The two city-states became rivals in banking as well as politics. 
Much of Siena’s wealth arose from the city’s position on a major pilgrimage route to Rome, the Via Francigena, which was also important for trade to and from the Eternal City. The Sienese enjoyed an unusually stable republican government, led by a legislative Council of Nine that was elected every two months, and balanced the power of the Podestà, or chief magistrate. Or it was stable until the Black Death of 1348. After that, the government fell apart, and although the city remained wealthy and enjoyed a brief flowering of prestige following the election of the Sienese noble Aeneas Silvius Piccolomini to the papacy as Pius II in 1458, Sienese culture was never again central in Europe. The most influential Sienese of the sixteenth century was the banker Agostino Chigi, the richest man in Rome, but he was a patron of artists, writers, and scholars, not a creator himself.  
Siena’s main contribution to civilization was in the visual arts in the late thirteenth and early fourteenth centuries, and it centered around the studio of Duccio, where the other three great Sienese painters all seem to have trained: Simone Martini, Pietro Lorenzetti, and Ambrogio Lorenzetti, younger brother of Pietro. Martini was in demand throughout Italy, working in Naples, Florence, Pisa, and Assisi before moving to the papal court at Avignon, where he died in 1344, aged sixty. The Lorenzetti brothers also worked all over Italy, both together and separately, until they both died at home in Siena of the bubonic plague in 1348. Martini and the Lorenzetti brothers spread the lessons of Duccio’s studio far and wide. 
There is not so much a single Sienese style in the fourteenth century as there is a range of approaches that tended towards loosening up the set of patterns and symbolic conventions that restrained artists in the Byzantine tradition from observing nature too closely. The Sienese didn’t reject stylization; they simply refreshed existing traditions by restoring the habits of perception and individual judgement to the creation of art. 
For an idea of what Duccio brought to the art of painting, look at his Madonna and Child in the Metropolitan Museum of Art—the Stroganoff Madonna, as it used to be known. Compare it to any Byzantine icon of Our Lady. We too rarely ask our Orthodox friends for a frank, honest reckoning of the gains as well as the losses involved with their approach to sacred art. To most of us, Duccio’s superiority seems self-evident; but are there reasonable grounds for making judgements on works of art based on something other than the perception of visible beauty? Of course there are, and we ought to talk about them more openly. Yet from a Catholic point of view it’s hard to see how a Byzantine icon would prove more fruitful as an aid to prayerful contemplation than this image by Duccio assuredly is. 
Look at how Our Lady’s very fingers seem alive—gentle, relaxed, and prepared to caress her Son, Who takes the edge of her white veil in His little fingers, as if to wipe a tear from her eye. The image is stylized and wholly conventional in most senses, yet Duccio somehow achieves the illusion of reality, even though baby Jesus, in accordance with the Byzantine manner, seems less a baby than a little man. Duccio’s rendering of Our Lady’s passive melancholy is enigmatic, and invites over-reading by the sort of art historian who cannot detach her analysis of the piece from the emotions it inspires in her. Is the Virgin Mary looking forward to the Crucifixion? Is that why her Son seeks tenderly to dry her eyes? If such thoughts consciously crossed Duccio’s mind, does that somehow make them irrelevant to how we might view his work? 
After a few minutes’ contemplation, the intellectual dilemmas posed by sacred art begin to come into focus.
The Stroganoff Madonna has a plain gold background in the Byzantine manner, but other outside influences are visible, and there was no need for Duccio to leave Siena to find inspiring examples of other ways to paint a Madonna and Child. Illuminated manuscripts in the Parisian Gothic style must have traveled down the Via Francigena and passed in front of his eyes: The modeling of drapery on this panel seems to reflect the contemporary French practice. On the other hand, the stylized architectural element in the Stroganoff Madonna suggests the possibility that Duccio might have traveled a little. 
Below the Virgin Mary is a low ledge, an elaborate-looking parapet in white marble accented in red that recalls those fictive cornices that frame Cimabue’s frescoes in the apse of the Upper Church of Saint Francis in Assisi. Is this a coincidence? If not, did Duccio need to travel to Assisi to adopt this element, or could he have simply imagined it through hearing a verbal description? Since we are not academic scholars, we can take our time asking these questions without feeling the need to answer them decisively.
Vasari’s biography of Duccio is largely useless, although it at least suggests plausibly that the painter visited Pistoia, Pisa, and Assisi to work. But the dates and attributions do not match the documentation that has been unearthed over the past two hundred fifty years or so. Duccio’s work is first documented in 1278, and he died before August 3, 1319; according to Vasari, Duccio was still alive in 1349. But Duccio was too “Byzantine” to interest Vasari and his assistants; also, he wasn’t from Florence, and Vasari was a Florentine supremacist. At least he recognized the artist’s importance.
Duccio’s only securely documented painting other than the Rucellai Madonna is the Maestà (Our Lady, Queen of Heaven), that was commissioned for the Duomo of Siena in 1308 and formally installed on June 9, 1311, after a magnificent procession around the city. The main panel depicts Our Lady enthroned, surrounded by saints including Ansanus, Victor, Crescentius, and Sabinus. This section alone was seven feet high and thirteen feet wide. The whole altarpiece was over sixteen feet high and featured paintings on both sides. For centuries, this was the largest altarpiece in Europe. It was also the first to be decorated on both the back as well as the front. 
The front predella depicted the childhood of Jesus in seven scenes, interspersed with panels of six prophets (Isaiah, Ezekiel, Solomon, Malachi, Jeremiah, and Hosea). Above the central panel was an image (now lost) of the Virgin Mary, flanked on either side by three panels with scenes from the life of Our Lady, and three half-figures of angels. The back side of the altarpiece featured panels of angels and scenes from the ministry of Jesus Christ, His Passion, Pentecost, and His appearances between the Resurrection and Ascension. The bottom of the main panel on the front featured the inscription “Holy Mother of God, be thou the cause of peace for Siena, and of life for Duccio because he painted thee thus.”
In 1506, this altarpiece was moved to a side chapel; in 1771 it was sawn in half and dismantled. Its panels were sold off; some have disappeared. Thirty-three panels are dispersed among ten collections in five countries. For Siena: The Rise of Painting, the National Gallery and the Metropolitan Museum of Art managed to bring together the eight surviving panels from the back predella showing the ministry of Christ: their first reunion in two and a half centuries. Together these represent not just Duccio’s greatest achievement but a triumph in the history of narrative painting. The compositions of these panels demonstrate an extraordinary variety and inventiveness that surely exceeds that of Giotto’s in the Scrovegni Chapel in Padua, at least in certain respects. 
These predella panels are not large, around twenty by twenty inches apiece. They depict Christ’s second temptation (in the temple); Christ’s third temptation (on the mountain); the calling of the Apostles Peter and Andrew; the wedding at Cana; the woman of Samaria; the healing of the man born blind; the Transfiguration; and the raising of Lazarus. The missing panel might have depicted either the baptism of Christ or His first temptation (in the wilderness). What survives is a tour de force demonstration of storytelling prowess, using color as well as composition. 
Perhaps the most “Byzantine” of these panels is The Transfiguration (National Gallery, London), with its gold-leaf background and simplistic composition. Yet the impressions of space, depth, and drama are all new. Mount Tabor is not merely a flat background. It has the special Duccio quality of being at once unrealistic and wholly convincing. You also see this in the Third Temptation (which is in the Frick Collection): The heavily stylized city depicted here is instantly recognizable as Siena, even though no Sienese landmark is identifiable.
In Duccio’s depiction of Christ and the Samaritan Woman, the well, Jacob’s Well, appears to be made of green porphyry and sits on a hexagonal or octagonal base. Its shape is implausible, like that of a balsa-wood model that has been crushed. Duccio appears to have done this purely to achieve visual harmony, both within this panel and across the entire predella. Incredibly, he gets away with it.
Duccio is parsimonious with realistic detail. Jesus and the Samaritan woman have unimpressive faces and hands, and Our Lord’s clothing has been rendered with more care than His right foot or hand, yet His unusual-looking left foot, the placement of His left hand on the well’s ledge, and the care given to every detail of the disciple’s faces, clothing, and nervous fingers as they look on from the side suffice to bring this image fully to life. 
Overall it is difficult to tell which of these seven panels is the most impressive, although the most perfect is surely the Raising of Lazarus (kept in the Kimbell Collection, Fort Worth), which surely surpasses attempts by Sebastiano del Piombo, Caravaggio, and Rembrandt to tell this story. Its only rival in this respect may be Giotto’s version in the Scrovegni Chapel. Taken in isolation, Duccio’s Raising of Lazarus may be the single strongest argument for the practice of stylization in sacred art: Duccio gives you just enough visual assistance to imagine the unimaginable, with immense economy and self-restraint. The artist feels no need to over-exert himself; his job is simply to remind you of the truth of the Gospels, not force you to see it as he sees it, or as he wants you to think he sees it (as Sebastiano del Piombo seems to be doing in his Raising of Lazarus in the National Gallery in London). 
Duccio was rare among Italian Old Masters in successfully training disciples who also became among the greatest painters of their age in their own right. Pietro Lorenzetti is celebrated for his extraordinary cycle of frescoes depicting the Passion in the Lower Church of Saint Francis at Assisi and his splendid Birth of the Virgin triptych altarpiece for the Siena Duomo from 1342, which achieves the illusion of depth and space as well as texture to a degree that few painters managed to attain before the development of perspective or the advent of oil painting in Italy. Pietro’s younger brother Ambrogio created one of the most intellectually interesting cycles of frescoes in the history of painting for the Palazzo Publico in Siena between February 1338 and February 1339. The Allegory of Good and Bad Government has never been equaled as an example of ambitious, original, intelligent civic art. 
Ambrogio was a more sensitive painter than his brother, as is demonstrated by his Madonna del Latte, with its uncommonly realistic hands of Our Lady as she nurses her heavy child, who squirms restlessly while He feeds. Yet Duccio’s finest disciple was surely Simone Martini, whom Vasari mistook for a pupil of Giotto’s. Martini became great friends with Petrarch when they both lived at Avignon; the loveliest testament to their friendship is the frontispiece that Martini painted for Petrarch’s manuscript of the works of Virgil that is now in the Ambrosian Library in Milan. Martini’s refinement and sense of finesse make him one of the most attractive painters in all Italian art. He surpassed Duccio in so many ways, but his achievements are unthinkable without the inspiration or originality of his master.
The catalogue of Siena: The Rise of Painting makes for an interesting comparison with that of the National Gallery’s exhibition in 2007, Renaissance Siena: Art for a City. From the 1350s onward, Sienese art degenerated into a pastiche of its masters. The traditions established by Duccio took a long time to die, but after the Black Death there was no vitality left in any of them. Sienese art became, in its way, as formulaic and programmatic as the Byzantine art that it replaced. Its artists became provincial, seeking inspiration and approval from more fashionable centers. Competent artists and artisans were still at work in Siena, but they were little better than decorators, too timid to make advances in their art or refresh their acquaintance with the fundamental insights of their forebears. They no longer believed in themselves or what they created. The plague had wiped out not just a generation but an entire tradition. 
Under such conditions it takes grace to find the strength to create beauty and glorify God in art. Artists today face a similar choice. They could be like the Sienese of Duccio’s day and create something radically new that breaks with all the exhausted, lifeless traditions of the past century and a half. Or they might forget about Duccio and his followers and choose the path of Siena after 1350: comfortable mediocrity.