Final answer:
Washington Irving is significant for his role as one of the first professional American writers and for shaping early American literature and culture, most notably through his work 'The Legend of Sleepy Hollow'.
Step-by-step explanation:
Washington Irving is a significant figure in the New World for his contributions as an author of early American literature. He is notable for his works, notably 'The Legend of Sleepy Hollow' (1820), which is among his writings found under the papers of the fictional historian Diedrich Knickerbocker. Irving's stories are a part of the American cultural lexicon and have heavily influenced the American literary tradition, infusing it with distinctively American elements of folklore and legend.
Often regarded as the first professional American writer, Irving helped to shape the identity of American literature separate from its European roots. His role in defining American culture and art during a time when the country was still finding its identity on a global stage renders him a pivotal figure in history. Additionally, Irving's ability to weave narratives that reflect the republican virtues and cultural values of his time contributed greatly to America's national character.