How did the US territory change from 1820-1830?

Between 1820 and 1830, the United States expanded its territory through various means, including the admission of new states and treaties. The Missouri Compromise of 1820 allowed Missouri to enter the Union as a slave state while Maine joined as a free state, maintaining the balance between free and slave states. Additionally, the U.S. continued to negotiate treaties with Native American tribes, leading to the cession of land as settlers moved westward. This period marked the beginning of significant westward expansion that would shape the nation's future.