Originally titled "Quarrel," "The Event" was written in 1962, and is plainly a commentary on Plath's deteriorating marriage to Ted Hughes. It was written following a visit from Assia Wevill, the woman Ted would eventually leave Sylvia for. During the visit, it became clear to Sylvia, who had just given birth to her second child, that there was a romantic connection between Ted and Assia.
The poem uses nature imagery to describe Plath's feelings. Her marriage is a "chalk cliff," her baby's face is "carved in pained, red wood." The poet walks in circles, her footsteps making "a groove of old faults, deep and bitter." Her soul is like "a small white maggot," and she wonders "who has dismembered us?"
Hughes felt the poem violated the "rules" in that it spoke too plainly about her unhappy marriage. It is true that the poem is visceral in its depiction of emotional helplessness, but it seems an almost involuntary reaction to her failing marriage. "Intolerable vowels enter my heart," Plath writes, and presumably they had to come out.