Does Fellini count as popular culture? It's a film, so I'm saying yes for now!
I've said many times that I don't generally criticise films for straying from the plot of a source novel or poem, or even from history (within limits). Since Petronius' Satyricon, a Latin novel, survives only in fragments and would require heavy editing and additional material in any adaptation, changes to plot and so on would be expected. What I don't like about Fellini's Satyricon, however, is that it completely changes the tone of the story. I suppose there's nothing wrong with that either, but I'm very fond of the novel and the film isn't really to my taste, so I'm afraid I've never really warmed to it! (The more wine I drank, the more it seemed to make sense, which tells you quite a lot about this film).
In fact, the film does incorporate nearly all the surviving elements of the novel, including the argument over Giton (Gitone) between Encolpius (Encolpio) and Ascyltus (Ascilto), Trimalchio's dinner (right down to the gag about the pig that's supposedly not been carved but actually contains sausages, his arguments with his wife, and his obsession with death and mock funeral) and Encolpius' impotence, for which he goes to a witch for help. In addition, elements of the festival of laughter come from the other surviving Latin novel, Apuleius' The Golden Ass, or Metamorphoses, which I also love (since that's about a man who turns into a donkey, I dread to think what Fellini might have made of it if he'd adapted that one!). The fact that there are many additional sequences is logical as well, since there are huge gaps in the novel that stop it from making any sense in places.
However, Fellini's additions are not designed to increase the film's narrative coherence. In fact, he liked the dream-like aspects of the novel in its fragmentary state and made the film deliberately dream-like. You'd think, as an expert on ancient dreams, I'd like this, but I'm afraid I don't. I like surrealist fine art (Dali etc) but I'm afraid I'm just not so keen on surrealist films. I like my films to have boring, pedestrian things like narrative and characterisation and plot development. (I do like dream episodes of TV shows, but that's about exploring new aspects of established characters. And they tend to be funnier).
The real problem for me, then, is simply one of personal taste - I prefer the tone of the novel to the tone of the film. The novel is a broad comedy - it reminds me of a Carry On film or perhaps a more modern sex comedy. It is certainly full of sex and occasionally a bit of violence and it includes lengthy sections about Encolpius' attempts to cure his impotence using witchcraft, but it's the sort of broad, rude comedy that, I think, isn't supposed to be taken particularly seriously. Fellini, on the other hand, makes it a disquieting production which uses sex in such a crude manner as to be positively off-putting. He fills it with confusion and anger, opening with Encolpio screaming his fury at Ascilto and Ascilto likening his activities with Gitone to Tarquin's rape of Lucretia, setting the scene for something designed to be unsettling in a way the novel was not.
(The tagline - 'Rome. Before Christ. After Fellini.' - annoys me too, since Petronius wrote after, not before, Christ. I'm nit-picky that way).
The other main theme totally missing from the film that was a major theme of the source novel is Encolpius' social and intellectual superiority and snobbishness. Encolpius is decadent and sex-driven, but he also laughs at freedmen, who are socially beneath him and don't know their myths, and at bad epic poets who are incapable of producing good artistic work. Perhaps Fellini's Encolpio is educated - he certainly seems rich and posh - but he wanders around in such a daze and much of the dialogue makes so little sense at all that you don't get any sense of his intellectual superiority. Petronius' Encolpius is an intellectual snob who tries to impress Giton as much with his brains and learning as anything else, but Fellini's Encolpio is interested solely in bodies. Eumolpus the terrible poet does appear in the film, but he talks about art, criticises Trimalcione's poetry, and Encolpio seems rapt, not scornful as he does so. His own poetry is recited in Latin so the audience can't follow it or appreciate whether it's good or bad. Intellectual snobbery and making fun of those socially below you may not be especially attractive traits, but this is another way in which the film tackles the plot from a completely different angle to the novel.
On the other hand, the use of vulgar Latin for lower status characters is a rather nice inversion of the book, and does hint at Petronius' snobbery, as we understand the upper class characters fully but only catch snatches of the lower class characters' dialogue (assuming we speak Italian, which is close to Latin. Which I don't, I confess, other than knowing how to order pizza - I do read Latin, but following spoken Latin is harder!).
There are some nice individual scenes here, and of course I particularly liked the scenes that contained, within themselves, a stronger sense of narrative and character. The scene with the couple freeing their slaves and committing suicide is rather touching and nicely done, and I like the story about the widow and the guard; plus the inclusion of stories within the story fits nicely with the novel, which includes several stories within the story (frequently involving ghosts and werewolves and similar tales).
The look of the film, however, is so very 1960s that it ends up resembling a particularly demented episode of Star Trek, especially the glowing green thing everyone's sucking from at Trimalcione's dinner, and the women who are painted blue. Sometimes I really do worry about what on earth everyone was up to in the 1960s... The rich colour palette is appropriate given the themes of richness and decadence, but it can be too much for me in places, and there's a fair amount of vaguely Oriental-looking imagery, which apart from being historically inaccurate (Rome had trade links with the Far East, but the amount of Oriental imagery here is rather too much) strikes me as mildly racist, given the context.
Like the book, Trimalchio's dinner is one of the best bits, and here there is some sympathy with Petronius' characters - Trimalcione's dialogue, as far as I can tell by the English subtitles, is a combination of slang and the sort of mad vocabulary produced by swallowing the thesaurus, which is recognisably the Trimalchio Petronius wrote. Trimalcione's stories about his time as a slave and his obsession with death and mock funeral are all from the novel too, and while they are creepier here, that actually fits, since we as a modern audience will have much more sympathy with Trimalchio and find his history more disturbing and his death obsession less pititful and more sad than Petronius (through main character Encolpius) does.
There are a few references to 'Caesar', and the Caesar they're describing sounds like Tiberius (retiring to an island to have sex with lots of young men), though Petronius (assuming he was indeed Petronius Arbiter, which I think he probably was) lived and wrote under Nero (and had more sense than to criticise him openly in his novel, not that that saved him in the end). The bit where the man playing at being emperor marries Encolpius, with himself (the fake emperor) as the bride is very Neronian though - according to Suetonius, Nero did the same thing with a young man. Nero was forced to suicide as well, like the young man who appears to be Caesar here (though he's too young, Rome didn't go for boy emperors, not until very late). The 'new Caesar' is a shadowy figure who doesn't appear, so who he's supposed to be, if anyone, is unclear.
What's really important about this film is how many standard 'Roman' popular culture tropes are present in it, their popularity enhanced by it. Everything's better with minotaurs for starters, even if this one is a man in a costume rather than an actual minotaur. This was far from the first film to suggest Romans had too much decadent sex, but its depiction of orgies is perhaps definitive. It takes the rich and glorious colours of films like Quo Vadis and makes them something almost sinister, with an emphasis on red, blood and blood-reds. We see animals being killed and their blood everywhere, because if you're focusing on harsher or more alien aspects of ancient life, you have to have animal blood (see also Gladiator). There's some fantastic imagery, like the weird giant-head-coach-thing with black horses, reminiscent of Hades' chariot as he abducted Persephone in myth. I also love the broken frescoes at the end of the film, which evoke the fragmentary state of the novel, emphasising the huge gulf of time between us and Petronius' characters, as well as the often random nature of the preservation of Classical texts. I'm still not wild about things that finish in mid-sentence though, even if I do see the point (and no, I don't like the Sopranos finale!)
Overall, however, I can't get over the fact that Fellini (deliberately, consciously) completely misses the point of the novel. The bizarre stipulation of Eumolpo's will, for example, that insists his heirs eat his flesh, is technically straight from the novel but with a totally different emphasis. The point of Eumolpus' strange will in the novel is that it's a 'take that' to the legacy hunters who are following him around, hoping to inherit his money when he dies (which he hasn't yet) - its a satirical joke, not the weird and rather gross demand it becomes in the film. All in all, surrealist film-making just isn't for me - though at least I do now have an alternative to The Passion of the Christ when I want to listen to some Latin!