If this interpretation is valid, then the polyptych of St. Vincent may very well have been conceived by Nuno Gonçalves as a piece of anti-Braganza political propaganda, one possible reason it might have remained hidden for years. It would also set up a "terminus post quem" for the creation of the panels; they would have to have been painted after 1449 (the date of the Battle of Alfarrobeira). That would tend to support the traditional belief that they date from the 1450s (when passions left over from that conflict would still have been fresh), however if the boy depicted in the Panel of the Prince can be identified as the future King John II (b. 1455), his height and appearance would certainly indicate a child older than five years' old, thus a date in the 1460s would be more likely.