Final answer:
New Orleans played a significant role in the economy of the growing United States in the early 19th century, primarily due to its involvement in the cotton trade and its strategic location near the Mississippi River. The city served as a major trading hub for cotton, which was transported on steamboats down the river and then shipped to England.
Step-by-step explanation:
In the early 19th century, New Orleans played a significant role in the economy of the growing United States. It rose in prominence and importance due to the cotton boom, steam-powered river traffic, and its strategic position near the mouth of the Mississippi River. New Orleans served as the primary trading hub for cotton, which was transported on steamboats down the river and then shipped to Liverpool, England. This lucrative international trade brought new wealth and residents to the city, making it a thriving metropolis.