I adore this film. The acting is outstanding, particularly that of Kenneth Brannagh. The way Brannagh has adapted Shakespeare is a little bit risky, particularly when he imports a bit of another play (Henry IV) to explain how the king has "broken the heart" of Sir John Falstaff - but some explanation had to be made. He also cuts out some other stuff that a 20th century audience might not find very appealing in this King whom Shakespeare wants to practically canonise: like the king's order for all French prisoners' throats to be cut at Agincourt (act IV scene 7). I think the alterations are acceptable. He leaves out one bit of gruesome dialogue I'd rather he had left in, when Henry makes a little speech to the French herald to emphasize the fact that he will not be ransomed and the only profit they'll get out of him are his "joints" (act IV scene 3). He goes on to say that any English corpses left on the field will kill twice over because "the sun shall greet them", they'll rot and choke the air, "killing in replapse of mortality". Neat!
Shakespeare's king is an ambivalent figure, and Brannagh brings this out well, although not in quite the same way as does Shakespeare. I particularly like the scene after the battle, when Henry carries a dead boy off the field, through the scene of carnage where the muddy puddles are red with blood, passing a group of three French princes, one dead, kneeling in a way that refers to a pieta.
Shakespeare/Brannagh's Henry seeks war, but sees it as his duty. The reasons he has for seeing war as his duty relate to a particular kind of naked patriotism that does not appeal to me, but that does not detract from the attractiveness of the character: it gives a sense of "otherness", of time having moved on: and actually you get the feeling that Henry himself has "moved on" by the end of the film. There's a sensitive portrayal of human behaviour in the face of death. And on the eve of Agincourt, Henry has an ethical discussion with some of his soldiers: if soldiers kill on the orders of the king while doubting the justice of his cause, do they stand exempt from blame?
Oh, I do like this film!