When Attila took possession of the royal palace of Milan, he was surprised and offended by the sight of a picture, which represented the Caesars seated on their throne and the princes of Scythia prostrate at their feet. The revenge which Attila inflicted on this monument of Roman vanity was harmless and ingenious. He commanded a painter to reverse the figures and the attitudes. And the emperors were delineated on the same canvas, approaching in a suppliant posture to empty their bags of tributary gold before the throne of the Scythian monarch.

From Edward Gibbon’s The Decline and Fall of the Roman Empire, London: Wordsworth, 1998 (first published from 1776 to 1788), p. 665.