Walt Whitman wrote the poem after Abraham Lincoln’s assassination. Repeated metaphorical reference is made to this issue throughout the verse. The “ship” spoken of is intended to represent the United States of America, while its “fearful trip” recalls the troubles of the American Civil War. The titular “Captain” is Lincoln himself, It is illustrated by a movie poster from “Birth of a Nation”. which shows John Wilkes Booth just having shot President Lincoln and making his escape.