The art historical literature generally asserts that the great Sienese painter cited in a document of 1320 as “Petrus quondam Lorenzetti” and who signed himself as “Petrus Laurentii” is to be identified with the Petruccio di Lorenzo paid in 1306 for a panel, now lost, painted for the Sienese government. If that is the case, then his date of birth is unlikely to have been any later than 1280. The prestigious commission presupposes, in fact, that he must have been a well-established artist by this date. On the other hand, Pietro’s first securely dated work is the polyptych in the pieve of Santa Maria in Arezzo, commissioned from him by the bishop of that city in 1320.
The lack of documentary evidence for any previous work has given rise to many uncertainties in the reconstruction of his period of apprenticeship and first phase of activity. However, there is now general consensus that his mural cycle in the transept and chapel of Saint John in the lower church of San Francesco in Assisi (two images of the Madonna and Child with saints, stories of the Passion of Christ, and Saint Francis receiving the stigmata) should be dated prior to 1320, though according to some authorities, their execution could have been prolonged into the third decade. A series of panel paintings may also be assignable to Pietro’s early career, including the signed Madonna and Child Enthroned and the great painted crucifix in the Museo Diocesano of Cortona; the Crucifixion in the Fogg Art Museum in Cambridge, Massachusetts; and the dispersed polyptych formed by the Madonna of Montichiello (now in the Museo Diocesano in Pienza) and the series of half-length saints divided between the Museo Horne in Florence and the Musée de Tessé in Le Mans. These works show Pietro to be a master of extraordinary ability who feels the influence of Duccio di Buoninsegna (Sienese, c. 1250/1255 - 1318/1319) but also shows his indebtedness to the compositional rigor, understanding of physical density, and monumentality of form of Giotto (Florentine, c. 1265 - 1337), as well as the passionate expressive charge of the sculptures of Giovanni Pisano.
The misread or mistakenly reconstructed date of some important works has also prompted discussion, or raised doubts, about Pietro’s career in the period of his maturity. His paintings for the Opera del Duomo in Siena in 1326 have been lost. Thus, a key work for reconstructing Pietro’s career in the third decade remains the polyptych signed and dated 1329 from the Sienese church of the Carmine (now divided among the Pinacoteca Nazionale in Siena, the Norton Simon Museum in Pasadena, and the Yale University Art Gallery in New Haven). To the same period art historians have assigned various precious panels of small dimensions as well as the frescoes in the chapter house of San Francesco in Siena, painted in collaboration with his brother Ambrogio. Fragments of the latter decoration survive that are attributable to Pietro’s hand, notably the Crucifixion and a figure of the risen Christ,exemplifying, according to Carlo Volpe, an “austere and severe style . . . that appears almost to contradict the chromatic and narrative gothic richness of the stories . . . of Assisi.” But the stylistic shift to which these paintings testify can perhaps be understood also as the response of the Lorenzetti brothers, on the basis of their Florentine experiences, to certain manifestations of the courtly-aristocratic art of Simone Martini (Sienese, active from 1315; died 1344) and Lippo Memmi (Sienese, active 1317/1347) in these years. Ambrogio is documented in Florence on several occasions between 1319 and 1332, while the presence even earlier of the still youthful Pietro in that city is testified by the Saint Lucy in the church of Santa Lucia dei Magnoli.
In the 1330s, the artist’s style underwent a further transformation under the influence of Pietro’s frequent collaboration with his brother, with whom he painted the frescoes, now lost, on the facade of the Ospedale della Scala, signed by both and dated 1335. From this partnership derives the artist’s greater attention to elegance of form and delicacy in chiaroscuro modeling that are also to be observed in the three saints, dated 1332, in the Pinacoteca of Siena. A further instance of the collaboration between the two brothers is the diptych (Madonna and Child and Crucifixion) now divided between the Gemäldegalerie in Berlin and the Fogg Museum, Cambridge, Massachusetts; Pietro executed the Madonna and Ambrogio the other leaf. One of the most significant testimonies of these years is the dismembered pala of Beata Umiltà, painted for the church of San Giovanni Evangelista in Florence. Now divided between the Uffizi, Florence, and the Gemäldegalerie in Berlin, it is an extraordinary example of Pietro’s sober narrative style and great poetic delicacy, though it is fair to say that scholars have not been unanimous in dating it nor even recognizing it as the work of his hand.
As for the artist’s final phase, few works datable to the 1340s are generally ascribed to the artist; some of them are sometimes given instead to an anonymous Dijon Master. Only the signed Madonna with a provenance from the church of San Francesco at Pistoia (Uffizi, Florence) and the altarpiece of extraordinary modernity with the Birth of the Virgin (Museo dell’Opera del Duomo, Siena), also signed and dated 1342, are undoubted autograph works of these years. The fresco (Annunciation andSaints) in the church of Castiglione del Bosco (Montalcino), dated 1345 and considered by various art historians to be the work of assistants, is the last work attributable to Pietro. It closes the catalog of his works in a minor key, with accents of almost rustic sobriety.
 Cf. Gaetano Milanesi, Documenti per la storia dell’arte senese, 3 vols. (Siena, 1854 – 1856), 1(1854):194. It was the Sienese custom to calculate the year ad incarnationem — that is, from March 25 — so the date cited in the document, February 25, 1305, is to be understood inmodern style as 1306.
 Carlo Volpe, Pietro Lorenzetti, ed. Mauro Lucco (Milan, 1989), 38.
 Ernest T. DeWald, Pietro Lorenzetti (Cambridge, MA, 1930), 30 – 31, and subsequently various other scholars have excluded this important painting from the catalog of Pietro Lorenzetti. Attribution is complicated by the fact that the original inscription, which probably contained the date of execution, was replaced in the nineteenth century by another bearing a date in Roman figures, sometimes read as 1316 and sometimes as 1341; cf. Miklós Boskovits, ed., Frühe italienische Malerei: Gemäldegalerie Berlin, Katalog der Gemälde, trans. Erich Schleier (Berlin, 1988), 85 – 89.
 Cf. Hayden B. J. Maginnis, “The So-Called Dijon Master: For J. R. Lander,” Zeitschrift für Kunstgeschichte 43 (1980): 121 – 138.
 The inscription of this painting, like that of the San Giovanni Evangelista altarpiece, has suffered restoration, and the date included in it has been variously read as 1315 or 1316 or 1340, or even assumed to have read 1343 in its original form; cf. Luisa Marcucci, Gallerie nazionali di Firenze, vol. 2, I dipinti toscani del secolo xiv (Rome, 1965), 157 – 158.
Miklós Boskovits (1935–2011)
March 21, 2016
DeWald, Ernest T. “Pietro Lorenzetti.” Art Studies 7 (1929): 131-166.
Cecchi, Emilio. Pietro Lorenzetti. Milan, 1930.
Sinibaldi, Giulia. I Lorenzetti. Siena, 1933.
Becchis, Michela. “Lorenzetti, Pietro.” In Dizionario biografico degli italiani. Edited by Alberto Maria Ghisalberti. 79+ vols. Rome, 1960+: 65(2005):803-811.
Carli, Enzo. I Lorenzetti. Milan, 1960.
Maginnis, Hayden B.J. “Pietro Lorenzetti: a Chronology.” The Art Bulletin 66 (1984): 183-211.
Volpe, Carlo. Pietro Lorenzetti. Edited by Mauro Lucco. Milan, 1989.
De Benedictis, Cristina. "Lorenzetti, Pietro." In Enciclopedia dell’arte medievale. Edited by Istituto della Enciclopedia italiana. 12 vols. Rome, 1991-2002: 7(1996):884-892.
Monciatti, Alessio. "Pietro Lorenzetti." In Pietro and Ambrogio Lorenzetti. Edited by Chiara Frugoni. Florence, 2002: 13-117.
Boskovits, Miklós. Italian Paintings of the Thirteenth and Fourteenth Centuries. The Systematic Catalogue of the National Gallery of Art. Washington, 2016: 222-223.