Niccolò di Ser Sozzo

His style is closest to that of Lippo Vanni and his sometime collaborator Luca di Tomme and is ultimately dependent upon the tradition of Simone Martini and, especially, the Lorenzetti brothers, in whose workshop he may have apprenticed.

His most celebrated and earliest documented work is an elaborate Assumption of the Virgin forming the frontispiece to the Sienese land and property registration book known as the Codex Caleffo (c. 1334), now found in the Archivio di Stato at Siena.

This work is inscribed in Latin "Nicholaus, Ser Sozzi de Senis me pinxit" (Niccolo di Sozzo of Siena painted me).

Among the several paintings attributed to his hand is a dismembered polyptych in the Pinacoteca Civica of San Gimignano, formerly in the nearby church of Monteoliveto, also featuring an "Assumption".

In addition to his "Assumption" from the "Callefo" in the Siena Archives, that city's library contains an antiphonary with four illuminations by Niccolò (Virgin and Child, Presentation, Baptism, Resurrection of the Dead).