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The use of the name "Trimalchio" in F. Scott Fitzgerald's novel, The Great Gatsby, is an allusion to "a character in the Roman novel The Satyricon by Petronius." The comparison is that Trimalchio (once enslaved, but now free ("freeman") is a man who has worked his way up in the world, having started with nothing. He is now very wealthy, and lives an ostentatious life. He spends his money freely when he entertains, providing gatherings that are unique and impressive, even "over the top." In the novel, the reference is to "Trimalchio's feast."
Trimalchio (and his dinner party) is mentioned in several other literary pieces, including Pompeii by Robert Harris, and H.P. Lovecraft's short story "The Rats in the Walls," among others.
There is a single mention of Trimalchio in F. Scott Fitzgerald's The Great Gatsby as his showy parties and background parallels that of Gatsby. [Trimalchio and Trimalchio in West Egg were among Fitzgerald's working titles for the novel.]
The comparison is that Gatsby provides the same kind of grand, ostentatious gatherings, but these are "romantic" interludes for Daisy's benefit.
For such an affair, servants may be released. The diction choice of “caravansary,” an inn for caravans in Persia, furthers the image of the rich, indulgent Trimalchio and reinforces the satiric intent of the reference.
The use of satire indicates that the parallel drawn between Gatsby and Trimalchio is not flattering towards Gatsby.