Although you cannot tell from my accounting of the premise above, The Court Jester is a comedy, and a very funny one at that. However, it does have a fairly complex plot in its early stages--all of the above is relayed within the first 10 15 minutes. This is a slow burner, but as such, the last hour at least is a very solid 10. It's unfortunate that a few minor flaws in the earlier sections of the film (including the complicated plot) caused me to rate The Court Jester as a 9 instead. The last half is so incredible that I wanted to give the film a 10 instead; perhaps on subsequent viewings (this is only the second time I've seen the film; the first was many years ago) the opening sections will work better for me.
As one of the earliest "VistaVision" films, The Court Jester looks gorgeous. It is full of lush, extremely saturated color. The few panoramic landscape shots are stunning and almost surreal. Most of the film is set within Roderick's castle, however, which is no less attractive visually. Producers/directors/writers Melvin Frank and Norman Panama and their crew certainly got the period setting right. The Court Jester is just as authentic feeling as Knights of the Round Table (1953) or The Black Knight (1954), both part of a popular trend of the era of Arthurian and related films, leading to this satire.
The cast is excellent, even if some members such severely underused, such as Carradine and to an extent Rathbone. Of course, The Court Jester is really a showcase for Kaye's considerable and diverse talents. Kaye was adept at quickly changing characters, as in The Secret Life of Walter Mitty (1947), and gets to put that skill to great use here, first in disguises, then as the jester, and most importantly, as a hypnotized pawn in a number of "games". Princess Gwendolyn's matron, Griselda (Mildred Natwick), finds cause to put Hawkins under a spell to make him fall in love with the Princess, making a finger snap the cue for his hypnotic transitions. This leads to a hilarious extended sequence where different characters are interacting with Hawkins for different covert ends--some fueled by mistaken identity--and continually snapping their fingers. Kaye as Hawkins as Giacomo has to keep toggling back and forth between two personalities, neither of which knows about the other. Meanwhile, complicated plans are being made which he is expected to follow. Even funnier is that despite himself, he basically manages to follow the plans.
It's a bit silly, but the humor in The Court Jester is all about silliness--it's appropriate for the titular role and more importantly, it's just plain funny. From the finger snapping sequence through the end of the film is one long build up with increasingly outrageous situations, until we finally arrive at pandemonium, complete with tens of acrobatic midgets battling a cadre of knights in a scene remarkably prescient of the anarchic screwball comedies of the latter half of the 1960s.
Kaye's vocal talents are also put to considerable use, both in songs and in rapid-fire, sometimes nonsensical alliterative rhymes. There are a number of very famous--and rightfully so--instances of the latter throughout the film including the "vessel with the pestle/chalice from the palace/flagon with the dragon/brew that is true" bit, which has oddly taken on a life of its own outside of the film, and which like all of the comedy throughout the film slowly builds up to a hilarious climax.
Kaye also does a lot of physical comedy, including my favorite bit--the super-fast knighting ceremony, and he even does a bit of mostly serious fencing with Rathbone. Watching The Court Jester can only make one lament that Kaye was not featured in even more films; he was extremely talented and very unique.
The Court Jester has influenced many later films, including such diverse works as Monty Python and the Holy Grail (1975) (and by extension Jabberwocky, 1977) and A Kid in King Arthur's Court (1995). But influence or not, this is a masterpiece despite its flaws, and should be viewed at least once by any cinephile worth his or her weight in purple pimpernels.