(b Arezzo, c.1350; d Arezzo, 1410/11). Italian painter, the most distinguished member of a family of artists (mainly goldsmiths) from Arezzo (hence the name Aretino). Spinello probably trained in Florence, perhaps under Agnolo Gaddi. He was the most prolific muralist of his time and undertook large fresco cycles all over Tuscany. The last of these was devoted to the Sienese pope Alexander III in the Palazzo Pubblico in Siena (1408–10); he was the first non-Sienese painter to work in the building.
Text Source: The Oxford Dictionary of Art and Artists (Oxford University Press)