The committee for the reform of the calendar
Biccherna panel, Siena, July 1582-June 1583
Siena, Archivio di Stato, n. 72
This painted panel celebrates the introduction of the Gregorian calendar, which replaced the old Julian calendar in Catholic countries on 4 October 1582. The reform was implemented by moving the date forward from 4 to 15 October. In this scene we see Pope Gregory XIII, enthroned, chairing the calendar committee.