Bloomsday is an odd sort of holiday. Every June 16, people around the world gather to commemorate the single day—June 16, 1904—described in James Joyce’s “Ulysses.” The celebrations begin in Dublin, where participants trace the wanderings of the novel’s protagonist, Leopold Bloom, through the city. They continue with pub crawls in Buenos Aires, dramatic reenactments in New Zealand, and a sweeping potpourri of festivities in New York: Bloomsday on Broadway, Radio Bloomsday, and A Rap Tribute to James Joyce.

Such gleeful celebration strikes me as peculiar for a book whose goal was, according to Joyce, “to keep the critics busy for 300 years.” Dense, intricate, and populated with obscure and wide-ranging references, the nearly 1,000-page tome is hardly Harry Potter.

Yet key to understanding this day’s popularity is the centrality of the organized readings of “Ulysses” throughout the day. Some groups attempt to barrel through the entire novel; others take turns reading aloud excerpts or chapters, dialogues or scenes.

For those die-hard Ulysses re-readers, such marathon readings are a chance to meet and mingle with other Joyce enthusiasts through the novelty of reading aloud. And for those who never managed to finish (or start) the book, they offer a kind of porthole into a rich but overwhelming literary landscape.

The stream-of-consciousness narrative that characterizes Ulysses becomes more manageable when spoken as opposed to read. Textual ambiguity—who’s speaking to whom, for instance—becomes more clear when the dialogue is voiced.

This particular oral tradition is only as old as the first Bloomsday, celebrated in Dublin in 1954. Yet the celebrations—as well as the novel itself—can be contextualized in a broader historical framework. They are continuations of an ancient conversation, adapting a literary current defined in large part by its emphasis on the spoken word: the Homeric oral tradition.

For centuries, Homeric scholarship carried on a lively debate over who exactly the author of “The Iliad” and “The Odyssey” was—the blind poet of legend, a scattered array of authors, or something else entirely. More recently, these arguments have subsided in favor of the theory that these epic poems have an oral origin, and that what we read today is only one version of a loose, constantly evolving verbal script.

The epithets that appear again and again in “The Odyssey,” sometimes almost irritatingly repetitive to the contemporary ear, suggest this mode of composition. Descriptions like ‘swift-footed Achilles,’ ‘grey-eyed Athena,’ and ‘great-hearted Odysseus’ formed an inventory of phrases of varying syllables, any of which a bard could call upon to complete a line within the strict demands of metrical form.

The result, then, was the sort of dynamism impossible to equal on the page, a story with a stable plot and consistent ingredients that was, nevertheless, slightly different each time it was told. For a largely illiterate audience, these recitations combined the comfort of repetition with the intrigue of the new—change in structure, originality within a framework.

Epic poems like “The Odyssey” ultimately became so popular that they were immortalized in papyrus, creating a literary tradition that never fully stopped mingling with its older, oral cousin. Joyce’s “Ulysses” stands at the other end of that literary tradition. It began not in the mouths of bards but in the pen of its lone author.

In writing “Ulysses” Joyce explicitly recalled Homer’s epic, most obviously in the title but also in the formal ordering of the chapters and the thematic framework of the (mock) heroic quest. Confronted with an audience that could not only listen, but also read, Joyce conceived of his work as a maximalist modernist project, wrestling with how far he could push the limits of language to reflect, and assign meaning to, reality. Central to this task was the attempt to capture and catalogue the sounds of everyday activity, transforming noise into symphony by writing it down.

The Bloomsday readings reverse this trajectory. “Ulysses” becomes a mere blueprint for the participants, a kind of schematic guide. From it comes a new oral tradition, a collection of voices and an expanding scope of interpretation, as readers reassume the role of bards.

—Victoria A. Baena can be reached at vbaena@college.harvard.edu.