Why might Shelley have capitalised the words "King of Kings," "Works," "Mighty," and "Wreck" in his poem "Ozymandias"?

You need to be aware that different text editions of this
poem may or may not have the capitalisation that you refer to. However, having said
this, it is always important to consider why some authors or poets choose to capitalise
certain words and not others. Capitalisation is another form of giving special emphasis
or meaning to particular words. You might like to think about what this tells us about
these words. Note how the capitalisation in the words "King of Kings," "Works," and
"Mighty" serves to heighten and emphasise the intense irony of the sign declaring the
incredible kingdom of Ozymandias. This of course is underlined by the capitalisation of
"Wreck," which refers to the actual state of the mighty kingdom of Ozymandias--now
reduced to nothing more than sand.

Thus capitalisation is
normally used by poets and authors as a form of emphasis, which can link particular
words to the overall theme or message of the text. Here, the capitalisation is used to
underline the irony of the sign that the traveller finds in the middle of the desert,
making this poem an excellent meditation on the ephemeral nature of
man.