Most poems about childhood know exactly what was lost: a garden, a parent, a summer. Dickinson's speaker doesn't. She remembers only the feeling of loss, "The first that I could recollect," and admits she was "Bereft... of what I knew not." The poem is about grief that arrives before its cause, and about an adult discovering, late and almost by accident, that she may have been pointing that grief the wrong way.
The first two stanzas make the child's sorrow oddly grand. She is "A Mourner" who "walked among the children," the one dark figure in a crowd at play, and the metaphor she chooses is political. She goes about "As one bemoaning a Dominion / Itself the only Prince cast out." The grammar is knotty. It could mean a kingdom mourning its only prince, or a prince mourning the kingdom he has been thrown out of. Either way, a small child's mysterious sadness is given the scale of a royal catastrophe. That is funny, since a kingdom with one prince is a very small kingdom, but it is also moving, because the poem takes the child's feeling as seriously as she did. Nobody around her could "suspect," so the royal vocabulary is the only dignity her grief receives.
The third stanza jumps to adulthood with a dry joke: "a session wiser / And fainter, too, as Wiseness is." A "session" sounds like a school term or a sitting of a court, so growing up becomes a short course of study. Wisdom, meanwhile, is "fainter." It thins the world out as it explains it. Even the word "Wiseness" feels slightly off, less a noble quality than a condition, like paleness. Yet the speaker still goes "softly searching / For my Delinguent Palaces." The word "Delinguent" suggests palaces that have defaulted, failed to turn up when they were due. The kingdom has been replaced by a bureaucratic problem, and the searching is quiet, even embarrassed, in that soft adverb.
The ending turns the poem over. A "Suspicion, like a Finger / Touches my Forehead now and then." The gesture could be a tap on the shoulder, a reminder, or even a blessing, and its lightness suits a thought the speaker can't quite hold. What it suggests is that she has been "looking oppositely / For the site of the Kingdom of Heaven." Judging by the wording, she has been searching behind her, in childhood, for something that may lie ahead. The phrase "Kingdom of Heaven" also seems to echo the Gospel language about children and heaven, and the earlier royal imagery, Prince, Dominion, Palaces, now lines up with it. The lost kingdom of the first stanzas may have been the same place all along. Whether Dickinson means a literal afterlife or something more private is left open, and the poem is better for it.
The form carries this uncertainty. The stanzas rhyme loosely on lines two and four, and the rhymes weaken as the poem goes on. "Recollect" and "suspect" match cleanly, and so do "about" and "out." By the third stanza "is" and "Palaces" only half-agree, and the last pair, "then" and "Heaven," are close cousins at best. The sound of the poem drifts out of true just as the speaker's sense of direction does. The lines are built on roughly four beats but sag and stretch, as if the meter can't settle. The dashes and odd capitals (Mourner, Dominion, Finger) make ordinary nouns look like allegorical figures, so the Finger that touches her forehead feels almost like a character who has entered the room.
What makes the poem lasting is its restraint. It never says what was lost, and it never claims the answer arrives, only a "Suspicion." In a few plain stanzas it reframes nostalgia, the habit of treating the past as the place where everything went missing. Dickinson suggests that the ache we trace backward might be a longing aimed forward, and she leaves that idea resting on the reader's forehead as lightly as a finger.