Platte County embraces an exceptional position in Missouri history. Excluded from the original state of Missouri, the Iowa, Sac, and Fox First Nations, in 1836, signed the Platte Purchase Treaty to terminate their claims, receiving $7,500, livestock, and cabins. The new purchase formed the counties of Andrew, Atchison, Buchanan, Holt, Nodaway, and Platte. On 28 March 1837, the Platte Territory officially opened to settlement.