wrong cover art posted by IMDb for this film
Confusingly, IMDb has posted the cover art for an entirely different film. The illustration shown here is for the 1992 production of Rossini's 1819 opera La Donna del Lago, performed at La Scala with Ricardo Muti conducting, and starring Rockwell Blake as Giacomo V, re di Scozia. The opera is based on Sir Walter Scott's poem The Lady of the Lake.
This of course has nothing at all to do with Luigi Bazzoni's 1965 film.