Yeats frequently referenced Irish myth and legend in his poetry. He belonged to, and was an important figure in, a wave of late nineteenth and early twentieth-century art that celebrated Irish culture and language, partially in the service of asserting Irish nationhood in the midst of the fight for independence from Britain. This poem is a prime example of Yeats evoking the Irish cultural tradition: Aengus (or Oengus) is a Celtic god of youth, poetry, and love. However, the work's evocation of this folkloric history is indirect, and Yeats avoids explicitly referring to any specific stories associated with Aengus. He uses the character as a baseline, from which to invent an entirely new story, albeit one full of the motifs of Celtic lore. Here, we will discuss several of the stories generally told about the figure of Aengus in the mythological tradition.
In Irish folklore, Aengus was the son of Dagda—himself the most important god in the Irish tradition. His mother was Boann, a river goddess. Because Boann was married when Aengus was conceived, legends describe the way that Dagda kept her pregnancy secret by manipulating time. Through this trick of altering time, Aengus was born on the same day as his conception. The grown Aengus is described as handsome and clever, often emitting a supernatural glow. Moreover, he was associated with springtime, new life, and rebirth, and was able to resurrect the dead through only the force of his breath. Aengus was also described as having a particular gift for wordplay. This gift, stemming from his association with poetry, is at the core of many legends surrounding him, including the story of how he obtained his inheritance.
In this story, Aengus is dismayed to discover that he has been excluded from his rightful inheritance—a piece of land, called Brú na Bóinne—by his father (in some versions, it is his stepfather rather than his father who slights him). Aengus, upset by this rejection, asks his father if he may spend "láa ocus aidche," or a day and a night, on the land. While his father assents, he is unaware that Aengus has tricked him with wordplay. In the Irish language, the phrase láa ocus aidche can mean "a day and a night," or, simply, "day and night." Therefore, Aengus is permitted to remain on the land day and night, meaning that it belongs to him. In this legend, poetic inspiration is not merely used for entertainment: it is a versatile, practical tool.
Of all the stories of Aengus, the one that Yeats comes closest to directly referencing is the tale of how he married Caer Ibormeith. In this legend, Aengus experiences vivid, recurring dreams about a beautiful girl. Devastated by his love, Aengus searched for the girl endlessly. He asked his parents as well as other gods for help finding her, but even these powerful beings are unable to determine her identity or whereabouts. Eventually, Aengus's half-brother Bodb Derg discovers the girl, along with 150 other girls, chained and imprisoned at Loch Bel Dracon. Aengus learns that these girls transform into swans at Samhain, the Gaelic festival marking the end of the harvest and the start of winter. Aengus learns that, if he can identify the girl from his dreams as a swan, he will be permitted to marry her. Because Aengus himself has the power to shapeshift, he simply turns into a swan himself, and then speaks to his beloved in a shared animal language—thus allowing him to identify and marry her.
Though it is only through the name Aengus that Yeats makes an explicit reference to this set of myths, his poem contains a number of subtle references to or similarities to the broader Aengus mythology. The clearest of these is the speaker's unending, determined search for an elusive woman—although Yeats's Aengus does not find victory as easily as the Aengus of folklore. Yeats's poem does not specifically reference dreams, but it contains a dreamlike mood and logic that tie it to the story of Aengus's dreams. Meanwhile, both the legends of Aengus and Yeats's poem heavily feature motifs of transformation, whether of a fish into a woman or a woman into a swan. Folklore here appears to inspire and suffuse Yeats's work, rather than to limit and determine it.
