"There interposed a fly,..."See in text(Text of the Poem)
The verb “to interpose” means to get in the way of or to place something in between things or people. Here, the fly interrupts this grave moment by disrupting the seriousness of the occasion with its buzzing. Its sudden presence also disrupts the momentous climax that the reader has been primed to expect: a fly appears in place of “the king.” Dickinson may also suggest that the fly itself is the king, which is a possible allusion to Beelzebub, a demon from Milton’s Paradise Lost that ranks next to Satan and has been adopted into Christian theology and popularized as the Lord of the Flies.
