Put simply, "The Gyres" is about an old man on the verge of death, as he reflects on his existence and the destruction of civilization around him. However, the poem is a bit more complicated than that.

Yeats frequently wrestled with the themes of generational differences between the old and the young. In his poems "Sailing for Byzantine" and "The Gyres," the narrator seems to come to the same conclusion: just as his generation ignored any wisdom of their elders, so does he now find himself ignored. The narrator for "The Gyres" takes a strange kind of comfort in the circling and repeating mechanisms of life. He knows that, soon, the younger generation will find themselves in his position.

These thematic concerns reveal a kind of apocalyptic revelry in Yeats's form. The burning of nations, like Troy (which he mentions), has a purging effect on evil, but it always comes back. Though great empires like Rome and Greece may collapse, others will rise in their place. These new nations will bring both good and bad and experience inevitable eventual destruction. Thus, life flows along in a spiral or gyre, regardless of anyone's self-important social status, history, or culture.