Melville without Milton
Like Shelley and Blake, Melville was charmed by the individualism and heroic striving of Milton’s Satan, and he imbued Ahab with the same sense of outsized self-mythologizing. His rereading of Paradise Lost during the composition of Moby Dick significantly altered the novel’s meaning and mythic scope. The extraordinary fact is that as late as 1849 (Moby Dick was published in 1851), Melville had yet to conceive of Captain Ahab and was focused instead on the non-epic bildungsroman of a shipmate called Ishmael. Take Milton’s Satan away from Melville and you can forget about the earthshaking achievement of Moby Dick.
The Writer as Reader: Melville and His Marginalia by William Giraldi
http://lareviewofbooks.org/essay/the-writer-as-reader-melville-and-his-marginalia