Old Western Border of the United States

Old Western Border of the United States. . , Platte Purchase Drive marks the site of the western border of the United States from 1821, when Missouri became a state, until 1837. Unlike today, the western border of Missouri was a straight line north from the confluence of the Missouri and Kansas rivers and along today's Platte Purchase Drive. On the west side was Indian Territory. , In 1830, President Andrew Jackson signed the Indian Removal Act, requiring all eastern tribes to move to new reserves west of Missouri. Six years later, the United States government acquired the land between the 1821 border and the Missouri River from the Iowa, Sac and Fox tribes through a controversial treaty known as The Platte Purchase. , The treaty was signed by Supt. of Indian Affairs William Clark, Iowa Chief Mo-hos-ca (a.k.a. White Cloud) and 26 other chiefs and warriors, becoming law in 1837. The three tribes were paid $7,500 and given provisions to help them move to reservations west of the Missouri River. Not only did the purchase force another tribal removal, but it angered abolitionists who saw it as a violation of the Missouri Compromise since it increased the area for holding slaves. , Before the purchase, Missouri was already the largest state in the Union. The acquisition of 3,149 square miles was as large as the states of Delaware and Rhode Island combined. Missouri is the only state to increase its land mass to this degree. The newly added northwestern corner of Missouri was divided into six additional counties: Andrew, Atchison, Buchanan, Holt, Nodaway, and Platte. , Today, Platte Purchase Drive where this marker stands continues to be the dividing line between the counties of Clay and Platte.