What is an explanation of each stanza and the literary techniques used in Auden's poem " The Shield of Achilles"?

In Auden's "The Shield of Achilles," the narrator initially describes a woman (she) looking over a man's shoulder. Given the title of the poem, we may initially assume the “he” here is Achilles. However, the final stanza will reveal that is not the truth. Behind the male figure depicted, “she” sees aspects of thriving life and civilization, but they are contrasted with the “artificial” wilderness and lifeless sky embossed on the shield that is described. This is a pattern of contrasts that will continue throughout the poem.
The second stanza goes on to further detail the barren nature of the images on of the shield. There is “[N]o blade of grass, no sign of neighborhood.” There is only “[A]n unintelligible multitude . . . [W]ithout expression.” Despite the masses depicted on the shield, there are only futile attempts to replicate human life.
In the third stanza, the narrator describes “a voice without a face” that is apparently issuing commands, as “they marched away enduring a belief/ Whose logic brought them, somewhere else, to grief.” This suggests the same level of distance from humanity which are contained within the images upon the shield; however, now the disconnect is it is associated with real people: soldiers somewhere nearby.
In stanza four, Auden uses refrain to bring us back to our central character, through whom we experience much of the poem. This time she again glances over “his” shoulder to see various images of beauty and sacrifice that are associated with Ancient Greek culture. Again, these things are contrasted with the images on the shield, but Auden waits to describe them in the next stanza.
In the fifth stanza, Auden moves into a scene of apathy and imprisonment. Toward the end of the stanza, the narrator describes “three pale figures” who “were led forth and bound/ To three posts driven upright in the ground.” This suggests that the three men are to be executed, perhaps tortured first, but also alludes somewhat to the crucifixion of Christ, as he was accompanied to his death by two other pale figures.
In stanza six, Auden describes the feeling of hopelessness within the three men sentenced to die, as “they were small/ And could not hope for help and no help came” and “they lost their pride/ And died as men before their bodies died.” While we do not know what these men have done, we do know they have been stripped of their pride and because of this were dead even while their bodies were still alive. This suggests a critical level of dehumanization, which helps to prepare the reader for the final few stanzas.
The beginning refrain returns at the start of the seventh stanza, this time accompanied by scenes of Greek artistic and athletic culture, and is contrasted with a stifled, “weed-choked field” on the shield.
In the penultimate stanza, the narrative then further focuses in on thematic concepts of loneliness and despair in the form of a “ragged urchin” and a solidary bird. These figures are juxtaposed with images of people together, but the images that are presented do not contain warm, communal moments. Rather, “girls are raped” and “two boys knife a third.” Thus, even in the moments where people come together, the result is nothing but further terror and despair.
In the final stanza, the identity of the “she” and “he” of the poem are revealed. The shoulder of the refrain belongs to Hephaestos (or Hephaestus, as it is more commonly spelled), the Greek God of the Forge and Fire. The “she” of the poem is Thetis, whose marriage to Peleus was one of the events that cause the Trojan War. Their union also resulted in the birth of Achilles, their son, who would be killed during the Trojan War. Understanding this allusion reveals the true tragedy of the poem, as here Thetis has commissioned the very armorer of the gods to craft a shield to protect her beloved son, yet even this shield will not be enough to protect him because Achilles is mortal, and vulnerable. She cries “out in dismay” at the images of despair that cover the shield because Hephaestos crafted them “to please her son, the strong/ Iron-hearted man-slaying Achilles.” This suggests that her son has little time for the vibrant images of life in Greece, but would rather prefer the muted, poor imitations of life depicted on a shield. In seeing the shield that was crafted to please Achilles, she comes to understand that Achilles’ has lost his humanity and his ability to see the beauty of the world. In this way, he too has “died” as a man as well, and his body will be soon to follow.