A little history, if you will. Territorial Growth 1820.
Maine is to be admitted as a free state, Missouri as a slave state.
Stephen Long heads an expedition to the area below the Missouri River, seeking to locate the source of the Red and Platte Rivers, and to explore the upper Arkansas River. Maine is admitted as the twenty-third state in the Union. After winning its independence from Spain, Mexico opens the route to Santa Fe, long closed to American trade. The Santa Fe Trail between Independence, Missouri and Santa Fe, Mexico is blazed by Missouri trader William Becknell . The trail becomes the principal avenue for manufactured goods and emigrants bound for Santa Fe and the Southwest.