Walt Whitman created a new kind of poetry that became a major force in world literature – free verse. Without rhymes, cadence, meters, or line length, it reflected the unstructured nature of society over four decades. Considered the epitome of the romantic movement, when humanism was taking root, it exalts the human, material world, and laid bare the free spirit of the age, unhindered by moral responsibility.

Whitman was part of the transcendentalism movement of the time, as well as realism in literature. He kept adding to the book over the decades, making it a unique snapshot of cultural history.