Luca di Tommè's career as a painter was based mainly in Siena and spanned some three and one half decades. Although there has been speculation that Luca made one or more trips to Umbria or the Marches in connection with some of his commissions, the evidence points to his almost continual presence in his native city, especially after 1373. Furthermore, there is no documentary evidence of his actual residence elsewhere. During the course of some thirty-five years as an artist and head of a prominent workshop he must have produced a great many paintings, of which a good-sized corpus survives, enabling us to draw certain conclusions regarding the sources of his compositions, influences on his style, and his maturation as an artist. In making an assessment of him I have divided his career into four parts, for convenience's sake. These division points are, of course, somewhat arbitrary and there are a number of themes common throughout his work. However, certain paintings or documents that seem pivotal to his evolution as an artist have dictated where breaks ought to be made. These considerations justify the devotion of three chapters to the first half of Luca's career, from 1356 to 1373, and only one chapter to the remainder. Furthermore, the bulk of his surviving paintings, and indeed some of his most important works, came from a period of a little over ten years ( 1362-1373).
The early phase of Luca's career is still shrouded in mystery, and I have followed earlier critics in using the date 1356 as a beginning, for the simple reason that this is the first reference to him that we have. There is no clear indication as to how he got his initial training, or with whom, or indeed, for that matter, how long he had been painting before he was enrolled in the local painters' guild in Siena. On the basis of his surviving work we see that his first efforts were on a modest scale and that he was deeply indebted to Pietro Lorenzetti, in particular, for his compositional and figural style--as evidenced by the Crucifixion in San Francisco (Pl. 7). Because of this influence, Luca's earliest paintings seem derivative and, hence, conservative. His figures--often based on Pietro's--are robust and solid, although occasionally awkward and indicative of an as yet immature understanding of anatomy.
On the other hand, his compositional sense was already very good--again as seen in the San Francisco Crucifixion. His figural groups balanced each other, worked well in the space within which they were placed, and often were bound together effectively by architectural or landscape elements in the background. Luca's subtle manipulation of color also played an important part in holding these early narratives together, as vibrant yellows were played off against bright reds or deep blues. In keeping with the Sienese decorative tradition, Luca advanced the use of line as a compositional and ornamental element, exploiting and developing this device in countless folds and hems throughout his professional life. His mastery of surface articulation extended to the use of punchwork, which appeared over and over again in halos and along the borders of panels, as well as in clothing and drapery. Finally, in some of the works from Luca's early phase, the painted frame was used to heighten illusion and create compositional nuances, as seen, for example, in his Flagellation (Pl. 5) in Amsterdam.
The 1362 Saint Thomas altarpiece (Pls. 11-1-13- 6) represents a new phase of Luca's activity. Luca's role in the work was clearly essential to its ultimate effectiveness as an image. Beyond this, however, is the fact that the altarpiece reveals a new sense of design that was extremely sophisticated at this point, and that was reaffirmed from then on, as at Rieti (Pl. 27), Cascina (Pls. 47-1-47-7) or at Venano (Pls. 48-1 and 48-2). An additional consideration in this phase of Luca's career is, of course, his brief partnership with Niccolò di Ser Sozzo, whose stylistic influence on Luca was a strong one, and aspects of which Luca assimilated gradually and melded with what he had learned from Pietro Lorenzetti.