Considering that the poem opens with descriptions of autumn and the "wither[ing]" plants around the lake, it's not surprising that the landscape and the people in it are colorless. But it is surprising when you tally up how many times the poet uses the word "pale," or synonyms for it. Why does he harp on the paleness? Let's take a look at some examples…
- Line 2: The unnamed speaker says that the knight is "palely loitering." We get the point that he's hanging out by the lake without an obvious purpose, and he's "pale." Read this line out loud: notice the repeated L sound in "Alone and palely loitering"? The consonance of the L sound makes the line sound musical (think, "tra-la-la-la-la-la!"), but it also draws our attention to those words, especially to the unusual use of "palely" as an adverb. The word "palely" also creates an internal rhyme with the words "ail thee" from line 1. Associating those words makes it clear that the knight's paleness has to do with whatever it is that is "ail[ing]" him.
- Line 9: We hear more about the paleness of the knight when the unnamed speaker uses a flower metaphor to point out the "lily" whiteness of the knight's face.
- Lines 37-8: The knight uses the word "pale" three times in two lines. He's describing the dream he had in the fairy lady's cave, and the "pale kings" and "pale warriors" that he saw. They're all "death pale," so now paleness is being explicitly associated with death.
- Lines 37-40: The repetition of the word "pale" in this stanza brings out the similarity between that word and the words "all," "belle," and "thrall." This consonance, or repeated sound, associates those words as we read them, making the reader pause to consider how the "belle dame" might be responsible for the "pale[ness]" of "all" the knights she has had "in thrall."