Picture it, Shmoopers: you're out in a forest one day, in the mood for some fishing. You whip out your nice fishing rod, dip it in a stream, and—hey look at that—you catch a trout (yummy). Just as you're about to fry that fish over the fire, though, it turns into a gorgeous, sexy girl. Just like that, the ugly trout with its button eyes and pouty mouth is now a Kate Upton-like goddess. What the what? Of course, you'd want that girl's number. So what if she used to be a fish?

Confused yet? Well, now you know what it's like to be Aengus in William Butler Yeats' "The Song of Wandering Aengus," published in his 1899 collection The Wind Among the Reeds. It's Aengus, our speaker, who's struck with love when the fish he catches in a stream turns into a beautiful girl. It's a weird set-up for a poem, for sure. So what is it that Yeats is trying to accomplish by writing a poem about this fantastic happening?

Well, Yeats is doing a whole lot of things, actually. On one level, it's a poem about love. On another, it's a poem that showcases Celtic mythology. (Yeats, who was an Irish poet, drew on Celtic mythology in a lot of his poetry, including this poem.) On still another level, it's a poem about the impossibility of attaining what we desire (Aengus, in Yeats' poem, never finds the beautiful girl). On yet one more level, it's a poem about, well, growing old.

To top it off, Yeats manages to squeeze all of these big themes into a poem that's only 24 lines long. There's a reason he's considered to be one of the greatest poets of the twentieth century: the dude knew how to write a poem.

We've all heard of leprechauns, those short little dudes in green suits. In Irish folklore, they're fairies who get up to all kinds of pranks and tricks. You're probably also familiar with the shamrock, the young clover leaf that's a symbol for Ireland.

Beyond leprechauns and shamrocks (and maybe the St. Patrick's Day Parade), though, you may not know much about Ireland or Irish folklore. In fact, Irish culture is rich and storied, with roots in Celtic mythology. This is why William Butler Yeats' "The Song of Wandering Aengus" is so interesting. Yeats is considered to be one of the greatest poets of the English language—and it just so happens that he was Irish.

Based on Celtic (or Irish) mythology, Yeats' "The Song of Wandering Aengus" gives us a great introduction to one of the famous myths of Ireland: the myth of Aengus, god of love and beauty, and his infatuation with a beautiful girl. So, the next time someone asks you what you know about Ireland, you can show how cultured you are by busting out this myth. Think of how impressed everyone at the St. Patrick's Day party will be.