Oh yes, we can look at this as a parable of the "hippies" and an anti-war, anti-establishment film (as if those are somehow "bad" things.) It is all that. Any director who cannot interpret through the lenses of his time is not a very good director. Zefferelli is a master at it. It may make the movies seem dated but that also is a sign of mastership as we see the life of Francis and also see life in the Vietnam era 1970s. The movie itself is hauntingly filmed in a dreamlike manner. It tells the story of Francis who we will later know as Saint Francis Of Assissi. It is not an attempt to tell the complete story of the saint, but to use episodes from his life to speak to the culture of the time. It is not a biography so much as it is an interpretation.
Review of Brother Sun, Sister Moon
