American poetry refers to the poetry of the United States. It arose first as efforts by American colonists to add their voices to English poetry in the 17th century, well before the constitutional unification of the Thirteen Colonies. Unsurprisingly, most of the early colonists' work relied on contemporary English models of poetic form, diction, and theme. However, in the 19th century, a distinctive American idiom began to emerge. By the later part of that century, when Walt Whitman was winning an enthusiastic audience abroad, poets from the United States had begun to take their place at the forefront of the English-language avant-garde.