On a June day in 1311 in Siena, the great altarpiece completed by Duccio di Buoninsegna (c. 1255–1319) was carried from workshop to cathedral in a procession, with candles and the ringing of bells. That a city should greet a painting so shows the sacred weight of painting in medieval society. The "Maestà" ("in majesty") was a multi-panelled work over two and a half metres wide, showing the enthroned Virgin surrounded by saints and angels; on its back were dozens of small scenes from the life of Christ.

Duccio kept the golden ground, hierarchical order, and sacred figures of the Byzantine tradition; but he added something new. His figures are not stiff and frozen; they carry soft facial expressions, gracefully curving folds of drapery, a silent emotion circulating among them. The line is fluid and musical, the colours delicate and rich. In the narrative scenes on the reverse, an effort to tell a story appears through space, architecture, and gesture.

Duccio is named alongside his contemporary, the Florentine Giotto; but their paths differ. Where Giotto gave figures weight, volume, and dramatic reality — the "solid" path of the Renaissance — Duccio chose the elegance of line, the delicacy of colour, and the fluidity of narrative. This became the distinctive voice of the Sienese school and spread, through masters like Simone Martini, into Europe and the International Gothic style.

Though the Maestà is today dismembered, its panels dispersed to museums around the world, its main body is in the cathedral museum in Siena. As Western painting moved toward the Renaissance it flowed in two streams: the volume of Florence and the elegance of Siena. Duccio is the founder of the second.