The owner of the painting The Madonna del Granduca held what title from 1805-1814?
Madonna del Granduca:  The painting belonged to Ferdinand III, Grand Duke of Tuscany, from whom it got its name. Ferdinand III, Grand Duke of Tuscany:  He was also the Prince-elector and Grand Duke of Salzburg (1803–1805) and Grand Duke of Würzburg (1805–1814).
Grand Duke of Würzburg