The novella is rife with allusions from antiquity forward, especially to Greek antiquity and to German works (literary, art-historical, musical, visual) from the eighteenth century on.
One important framework of references points to Greek mythology; Aschenbach's Venice seems populated by the gods. By dedicating himself to Apollo, whom Friedrich Nietzsche's The Birth of Tragedy took to represent restraint, form and the intellect, Aschenbach has denied the power of Dionysus, Nietzsche's god of unreason and of passion – a voluntary act of what Freud would call "suppression". Dionysus seems to have followed Aschenbach to Venice with the intent of destroying him: the red-haired man who keeps crossing von Aschenbach's path, in the guise of different characters, could be a figure of Silenus, Dionysus's mythological chief disciple. In the Benjamin Britten opera these characters (the traveller, the gondolier, the leading player and the voice of Dionysus) are played by the same baritone singer, who also plays the hotel manager, the barber and the old man on the Vaporetto. The trope of placing classical deities in contemporary settings was popular at the time when Mann was writing Death in Venice: in England, at almost the same time, E. M. Forster was at work on an entire short-story collection based on this premise. The idea of the opposition of the Apollonian and Dionysian was first proposed by Nietzsche in The Birth of Tragedy and was also a popular motif of the time.
Aschenbach's name and character may be inspired by the homosexual German poet August von Platen-Hallermünde. There are allusions to his poems about Venice in the novella and, like Aschenbach, he died of cholera on an Italian island. Aschenbach's first name is almost an anagram of August, and the character's last name may be derived from Platen's birthplace, Ansbach. However, the name has another clear significance: Aschenbach literally means "ash brook". The novella's physical description of Aschenbach was based on a photograph of the composer Gustav Mahler. Mahler had made a strong personal impression on Mann when they met in Munich, and Mann was shocked by the news of Mahler's death in Vienna. Mann gave Mahler's first name and facial appearance to Aschenbach, but did not talk about it in public. (The soundtrack of the 1971 film based on the novella made use of Mahler's compositions, particularly the "Adagietto" 4th movement from the Symphony No. 5). Alternately, Aschenbach's name may be an allusion to Wolfram von Eschenbach, the author of the Middle High German medieval romance Parzival, whose reimagining and continuation of the Grail Quest romance of Chrétien de Troyes contained themes similar to those found in Mann's novella, such as the author's fascination with and idealization of the purity of youthful innocence and beauty, as well as the eponymous protagonist's quest to restore healing and youthfulness to Anfortas, the wounded, old Fisher King. Given Mann's own obsession with the works of Richard Wagner, who famously adapted and transformed von Eschenbach's epic into his opera Parsifal, it is possible that Mann was crediting Wagner's opera by referencing the author of the work which had inspired the composer.
Modris Eksteins notes the similarities between Aschenbach and the Russian choreographer Sergei Diaghilev, writing that, even though the two never met, "Diaghilev knew Mann's story well. He gave copies of it to his intimates." Diaghilev would often stay at the same hotel as Aschenbach, the Grand Hotel des Bains, and take his young male lovers there. Eventually, like Aschenbach, Diaghilev died in Venice.