The poem
A sudden blow: the great wings beating still Above the staggering girl, her thighs caressed By the dark webs, her nape caught in his bill, He holds her helpless breast upon his breast.
How can those terrified vague fingers push The feathered glory from her loosening thighs? And how can body, laid in that white rush, But feel the strange heart beating where it lies?
A shudder in the loins engenders there The broken wall, the burning roof and tower And Agamemnon dead. Being so caught up, So mastered by the brute blood of the air, Did she put on his knowledge with his power Before the indifferent beak could let her drop?
September 1923

It's not my comment but better not to have any comment for this poet:) Like "The Second Coming," "Leda and the Swan" describes a moment that represented a change of era in Yeats's historical model of gyres, which he offers in A Vision, his mystical theory of the universe. But where "The Second Coming" represents (in Yeats's conception) the end of modern history, "Leda and the Swan" represents something like its…
Read the whole commentIt's not my comment but better not to have any comment for this poet:)
Like "The Second Coming," "Leda and the Swan" describes a moment that represented a change of era in Yeats's historical model of gyres, which he offers in A Vision, his mystical theory of the universe. But where "The Second Coming" represents (in Yeats's conception) the end of modern history, "Leda and the Swan" represents something like its beginning; as Yeats understands it, the "history" of Leda is that, raped by the god Zeus in the form of a swan, she laid eggs, which hatched into Clytemnestra and Helen and the war-gods Castor and Polydeuces--and thereby brought about the Trojan War ("The broken wall, the burning roof and tower, / And Agamemnon dead"). The details of the story of the Trojan War are quite elaborate: briefly, the Greek Helen, the most beautiful woman in the world, was kidnapped by the Trojans, so the Greeks besieged the city of Troy; after the war, Clytemnestra, the wife of the Greek leader Agamemnon, had her husband murdered. Here, however, it is important to know only the war's lasting impact: it brought about the end of the ancient mythological era and the birth of modern history.
Also like "The Second Coming," "Leda and the Swan" is valuable more for its powerful and evocative language--which manages to imagine vividly such a bizarre phenomenon as a girl's rape by a massive swan--than for its place in Yeats's occult history of the world. As an aesthetic experience, the sonnet is remarkable; Yeats combines words indicating powerful action (sudden blow, beating, staggering, beating, shudder, mastered, burning, mastered) with adjectives and descriptive words that indicate Leda's weakness and helplessness (caressed, helpless, terrified, vague, loosening), thus increasing the sensory impact of the poem.