Siena: The Duomo

Facade of the Duomo.

My first visit to Siena was in 2010. It was a rainy day and we got lost on the way to the city centre (which is quite an achievement: Siena is not that big). We had lunch at a mediocre restaurant that served factory-made tiramisu, which really should be a capital offence in Italy. Although there was more rain after lunch, things were alright again when we reached the Piazza del Duomo. Siena’s beautiful cathedral of Santa Maria Assunta, dedicated to the Assumption of the Virgin, is truly one of the most amazing Gothic basilicas in Italy. It was well worth a second visit. We returned to Siena in June 2016 and enjoyed our tour of the Duomo just as much as the first time.

History of the cathedral

Surprisingly, the early history of the Duomo is not well documented. Tradition dictates that there used to be a Roman temple dedicated to Minerva at this site, which was ultimately replaced by a Christian church in the ninth century. Pagan origins of Christian buildings are a popular theme, but often evidence is lacking, as we have seen in Florence. As far as I know, the Minerva hypothesis is as yet unsubstantiated. Construction of the present Duomo seems to have started in the middle of the twelfth century. Another tradition claims that the new cathedral was consecrated in 1179 by Pope Alexander III (1159-1181), who was born Roland of Siena (for details of his life, see this post). Documentary evidence about the construction of the Duomo is available from December 1226 onwards. For instance, in 1227 the Comune of Siena paid the Opera del Duomo for the purchase of the famous white and black (or actually dark green) marble that was used to decorate the interior and exterior of the cathedral.

Side view of the Duomo.

Documents from 1259 show that Nicola Pisano (ca. 1220-1284), known for his work in Pisa, was involved in the project, while in 1263 lead was purchased for the construction of the dome of the cathedral. This suggests that by then the cathedral was more or less finished. Nave, aisles, transept, choir and apse would have been completed by this time, and the addition of a dome was the cherry on the cake. The dome we see today is not as ingenious or impressive as that of the Duomo in Florence, nor is it the original thirteenth-century construction. The present dome was constructed in 1385 and the lantern was added in 1666-1667. It was designed by the famous architect and sculptor Gian Lorenzo Bernini (1598-1680).

Sculptures surrounding the rose window.

Interior of the dome.

Work on the facade began in 1284. Giovanni Pisano (ca. 1248-1315), Nicola Pisano’s son, was in charge of the project until his departure or dismissal in 1297. Pisano and his workshop sculpted the statues of angels, prophets, evangelists, Sibyls and Greek philosophers like Plato and Aristotle. All statues have long ago been replaced with copies and some of the originals can be admired in the Duomo museum. Camaino di Crescentino (ca. 1260-1337/8), also responsible for the baptistery underneath the cathedral choir, took over in 1299 and completed the facade by 1317. His more famous son Tino di Camaino participated in the project as well. Above the central portal we see the same IHS symbol that is also present on the facade of the Palazzo Pubblico elsewhere in Siena. It refers to the Name of Christ – IHSOUS in Greek – and was devised by the Franciscan missionary Saint Bernardino of Siena (1380-1444).

The large central rose window is impressive. The scene on the stained glass can however only be admired from inside the cathedral. It features the Last Supper and was executed by Pastorino dei Pastorini (1508-1592), a student of Guillaume de Marcillat, whose work in Arezzo we have discussed previously. High up on the facade are three triangular pediments with mosaics. These mosaics are relatively recent additions. They were made in 1878 in Venice and show the Presentation of Mary in the Temple, the Coronation of the Virgin and The Nativity of Jesus. The designer was Alessandro Franchi (1838-1914). The central bronze door is even younger. It is the work of Enrico Manfrini (1917-2004) and was installed in 1958. Note that the facade not only uses the standard white and dark green marble, but also a little pink. The cathedral’s elegant bell tower is 77 metres high. It was completed in 1313.

Last Supper – Pastorino dei Pastorini.

Unfinished nave.

In the 1330s, Siena was at the height of its power. It was a mercantile giant with a population of over 40,000. In 1339, the city government decided to enlarge the Duomo. In previous years, the choir of the cathedral had already been prolonged, but now the Sienese drew up plans to construct an entirely new nave with side aisles to the east of the Duomo. The plans involved changing the orientation of the basilica: the existing nave and aisles were to become ‘just’ the transept of the gigantic new cathedral. The project proved to be a classic case of hubris. The architect Lando di Pietro was put in charge, but seems to have died just a year later. Giovanni di Agostino (ca. 1310-1348?), known for his work in Arezzo, took over and managed to complete part of the new facade and nave. However, in 1348 the Plague struck and decimated the population of Siena. Giovanni may very well have been one of the victims.

The Black Death was an eye-opener for the surviving Sienese: in 1357 they decided to abandon the project. The partially finished right aisle nowadays accommodates the Museo dell’Opera Metropolitana del Duomo or Duomo museum. From the museum, you can climb the Facciatone, the unfinished new facade, which offers a wonderful view of Siena and the surrounding countryside.

Exploring the Duomo

Interior of the Duomo.

Once inside the Duomo, it is quite easy to feel overwhelmed. The colourful interior of the cathedral is simply amazing. The Santa Maria Assunta has a length of 89.4 metres. It is worthwhile to walk up and down the nave first, and look up every now and then. Take a look for instance at the internal decoration of the dome, executed between 1481 and 1494 (see the image above). The high altar is the work of Baldassare Peruzzi (1481-1536), the architect who also designed the Villa Farnesina in Rome. On it is a large bronze tabernacle by Lorenzo di Pietro, nicknamed Il Vecchietta (“old woman”) and known for his frescoes in the baptistery. The tabernacle was originally in the church of the Ospedale di Santa Maria della Scala on the other side of the Piazza del Duomo. It was made between 1467 and 1471.

The original apse window was the work of Duccio di Buoninsegna (ca. 1255-1318/19). Its central scene shows the Assumption of the Virgin. The beautiful stained glass window was made in 1287-1288 and can be considered one of the oldest windows still in existence. Small wonder that the Sienese cherish it and have moved the original window to the Duomo museum, replacing it with a copy.

The sanctuary.

Duccio certainly had a strong presence in this part of the basilica: his Maestà (1308-1311) was on the high altar for almost two centuries before being judged too old-fashioned and removed in 1506. In the eighteenth century, it was ejected from the Duomo and regretfully sawn up. Fortunately, it was reassembled again in the 1950s and can now be admired in the Duomo museum (although some panels are lost). Apart from the altarpiece, the choir and apse had been left undecorated. Domenico Beccafumi (1486-1551) was ultimately hired to fresco the apse, while Ventura Salimbeni (1568-1613) painted frescoes for the choir. The first series was completed in 1535-1544, while the second was executed between 1608 and 1611. Beccafumi’s frescoes were damaged by an earthquake in 1798 and partially replaced with new works.

The floor

The exquisite marble floor is one of the undisputed highlights of the Duomo. It is so important that the price of a ticket actually depends on how many of the 56 panels can be admired. The marble panels are, of course, quite vulnerable and many of them are covered for most of the year. I visited the Duomo in May of 2010, June of 2016 and January of 2024, and was fortunate enough to be able to see many – but not all – of them in full glory. The panels were made between the middle of the fourteenth century and the eighteenth century. Over forty artists participated in this huge project. Almost all of them were from Siena, the Umbrian painter Pinturicchio (1452-1513) from Perugia being the notable exception. He made his panel of the Hill of Wisdom, featuring a scantily-clad personification of Fortune, in 1505. We have previously seen Pinturicchio’s work in the Piccolomini Library, to which I dedicated a separate post.

Lupa Senese (replica).

Liberation of Bethulia – Urbano da Cortona (1473).

Slaughter of the Innocents – Matteo di Giovanni (1481).

Hermes Trismegistus – Giovanni di Stefano (1488).

Hill of Wisdom – Pinturicchio (1505).

Cumaean Sibyl.

In making the panels, two different techniques were used: sgraffito painting and marble intarsia or inlaid marble. Examples of the former can be seen on the Palazzo degli Anziani in Pisa. The technique involves using chisels and drills to carve and scratch out drawings on white marble and then filling the lines with black stucco. Marble intarsia is a bit more advanced and involves using different kinds of coloured marble.

The oldest panel in the cathedral is presumably that of the Lupa Senese, the she-wolf of Siena. It dates from 1373, but the panel we see today is actually a nineteenth-century reproduction. Apparently, pieces of the original can be seen in the Duomo museum, but I must have missed them on both of my visits to Siena. Anyway, even the reproduction is quite interesting. In the centre we see the she-wolf suckling Aschius and Senius, the sons of Remus and the traditional founders of Siena. Of course, the story about the origins of the city was plagiarised from the Romans. Surrounding the central tondo of Siena are eight more tondi with the Latin names of other cities in Italy. They are, starting at the top and going around clockwise: Arezzo (Arretium), Orvieto (Urbs Vetus), Rome (Roma), Perugia (Perusium), Viterbo (Viterbium), Pisa, Lucca (Luca) and Florence (Florentia). In the corners of the panel, there are four more tondi with the names of Grosseto, Pistoia, Volterra and Massa Marittima.

Nicola Pisano’s pulpit.

Also included in this post is the depiction of Hermes Trismegistus by Giovanni di Stefano (ca. 1444-1511), executed in 1488. The Liberation of Bethulia, a Biblical city mentioned in the Book of Judith, was made in 1473 and is attributed to Urbano da Cortona (ca. 1426-1504). The huge panel of the Slaughter of the Innocents, the horrible infanticide ordered by King Herod according to Matthew’s Gospel, is also included. It is the work of Matteo di Giovanni (ca. 1428-1495) and dates to 1481. Other artists who provided the cathedral with panels were Il Sassetta (ca. 1400-1450), Neroccio di Bartolomeo de’ Landi (1447-1500), Antonio Federighi (ca. 1420-1483) and the aforementioned Domenico Beccafumi.

The pulpit

Nicola Pisano’s pulpit is among the oldest objects in the cathedral. It was made between 1265 and 1268. By that time, Pisano was already a well-known artist, famous for having sculpted a similar pulpit in the Baptistery in Pisa. The Siena pulpit is octagonal, and has seven scenes depicting episodes from the Life of Christ. When I visited the Duomo in 2016, it was undergoing restoration and was hardly visible because of the scaffolding. Fortunately, I still had a photo from my visit back in 2010, while in 2024 the pulpit could be admired in full glory again. It shows two scenes from the Last Judgment, with the Blessed on the left (i.e. on Christ’s right) and the Damned on the right. Pisano’s pulpit has its own pages on Wikipedia, in English and in Italian.

Nicola Pisano’s pulpit (detail).

The Piccolomini Altar

The Piccolomini Altar.

The Piccolomini Altar is located in the left aisle, just before the entrance to the Piccolomini Library. The altar was commissioned by cardinal Francesco Todeschini Piccolomini (1439-1503), the archbishop of Siena and future Pope Pius III. The monument was meant as a tribute to his uncle, Pope Pius II, who had died in 1464, and also served to stress the importance of the Piccolomini family in the political and religious life in Siena. The Lombard sculptor Andrea Bregno (ca. 1418-1503) was hired to execute the project. Bregno worked on the altar from 1481 until 1485, and then seems to have suffered a breakdown. The central altar had to be finished by assistants from his workshop and no statues were ever made. The cardinal then zealously searched for an artist to sculpt the statues for the niches, but his first choice Pietro Torrigiano (1472-1528) only managed to do a statue of Saint Franciscus for the top part of the altar.

Fortunately for Francesco Piccolomini, he managed to ensnare a very talented young artist from Florence, who sculpted four wonderful statues for the altar. The name of this artist was Michelangelo Buonarroti (1475-1564). Between 1501 and 1504, he made statues of Saints Peter and Paul for the lower part and of Saints Pius (or Augustinus) and Gregorius the Great for the middle part of the altar. Michelangelo’s fame was already growing rapidly in those days and he was offered much more interesting commissions. Ultimately, the niche in the top right corner was left empty and the altar was never really finished. An older statue of the Madonna and Child, probably the work of Giovanni di Cecco and dated to circa 1371, was installed in the central upper niche. The altarpiece, also of a Madonna and Child, is attributed to Paolo di Giovanni Fei (1345-1411) and was executed circa 1385.

The Popes

The Duomo has an exceptional collection of busts of popes, which can easily be missed if you forget to look up every now and then. It starts above the apse and then goes clockwise around the entire cathedral. There are 172 busts in total, starting with Jesus Christ and Saint Peter, and ending with Pope Lucius III, who died in 1185. In his book about the popes, John Julius Norwich claims that it is not entirely clear when the busts were sculpted, but that the end of the fourteenth century is a good guess. I think Norwich is off by about a century. Other sources point to the end of the fifteenth century or the beginning of the sixteenth, possibly between 1495 or 1497 and 1502. The stucco busts all look more or less identical. It seems the sculptors used only a handful of molds, which makes the series intriguing rather than beautiful.

The Popes. Fourth from the left is Pope Alexander III, founder of the cathedral.

Pope Lucius III, Jesus Christ and Saint Peter.

What is curious about the series is that there seems to be no reason for it to end with Pope Lucius III. The pope before him was Alexander III (1159-1181), who was not only from Siena itself, but is also credited with consecrating the Duomo in 1179 (see above). One reason for the inclusion of Lucius might be that the collection originally contained a bust of the fictional female Pope Joan. Her bust allegedly had the inscription “Ioannes VIII Foemina de Anglia”, “woman from England”, as legend dictated she was born there. The bust was presumably removed during the pontificate of Pope Clemens VIII (1592-1605) and may have been either destroyed or given a new inscription (Pope Zachery is a possibility, according to Norwich; see below). It is not inconceivable that the removal of Pope Joan left a gap, which was filled by Pope Lucius III.

The Popes.

The Popes.

My travel guide to Florence and Tuscany provided some basic information about the Duomo. The website of the Opera della Metropolitana di Siena gave additional information about both the cathedral and the floor. Wikipedia has a detailed and well-referenced article about the Duomo. For Pope Joan and the series of busts, see John Julius Norwich, The Popes, Chapter VI.

Updated 14 April 2024.


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