Through a specific study of the sparimento of the frescoes painted in the Sala dei Cento Giorni by Giorgio Vasari in 1545 for cardinal Alessandro Farnese, this paper intends to emphasise the problem of the function of margins in this decorative cycle.

Art historians have generally drawn attention to the narrative scenes painted in the frescoes, whose subjects illustrate the episodes from the pontificate of Paul III. The present study, on the contrary, focuses on the margins of those representations. In Vasari’s frescoes, the peripheral painted architecture is populated with personifications of virtues. The distribution of these significant figures within the fake architecture ensures the effectiveness of the rhetorical system – planned by the historian Paolo Giovio – centred on Paul III as ideal pope.

This framing structure is, in fact, comparable with a theatrical bocca di scena that encircles the painted storie. The relationship between Vasari frescoes and contemporary theatre architecture has been already pointed out in previous studies of the subject; but the parallel is not simply a morphological one. The relationship is also relevant in the narrative sections of the frescoes: they do not show actual events of the pontificate of the Farnese pope, but rather present his likely deeds related to the Aristotelian concept of verisimilitude. Reconsidered by L. Castelvetro in the 1570s, this notion becomes central in the theory of Poetics but also in the development of modern drama. Vasari’s sparimento participates in and activates the iconographical programme devised by Giovio, adding to it a supplementary dimension in pointing out the illusionistic power of Painting and Theatricality. On the walls of the Cancelleria, histories (exempla virtutis of the Farnese pope) become History taking advantage of the framing structure and the figures placed within it.