1818 treaties between the United States government and six Native American peoples
Six 1818 treaties at St. Mary's transferred most of central Indiana from Native nations to the United States, pushing the state's effective boundary north to the Wabash River.
Key Facts
- Number of treaties
- 6
- Year concluded
- Fall 1818
- Primary tribe involved
- Miami (main tribe of Indiana)
- Land area acquired
- New Purchase — substantial portion of Indiana
- Northern boundary shift
- Near Ohio River to Wabash River (northwest and north)
- Preceded by
- Treaty of Greenville, 1795
By the Numbers
Location
Cause → Event → Consequence
Following the Treaty of Greenville (1795), the United States government continued a policy of acquiring Native lands in the Old Northwest. By 1818, pressure to open central Indiana for American settlement led U.S. commissioners to negotiate simultaneously with the Miami, Delaware, Potawatomi, Wea, Wyandot, and related peoples who held claims to the region.
In fall 1818, six treaties were concluded at St. Mary's, Ohio, between the United States and six Native nations of central Indiana. The agreements transferred a large tract of land—known as the New Purchase—to the United States in exchange for cash payments, salt, sawmills, and other goods. The Miami held the primary claim, and the treaty with them is considered the principal agreement.
The treaties shifted Indiana's effective northern settlement boundary from near the Ohio River to the Wabash River, opening vast tracts for American settlers. They also established Indian reservations within Indiana and accelerated the process of Native removal from the state, continuing a displacement pattern that would intensify over subsequent decades.
Political Outcome
United States acquired the New Purchase land area of central Indiana; Native nations received cash, goods, and services; Indian reservations were created and removal process advanced.
Native nations held title to most of central Indiana; U.S. settlement boundary near Ohio River
United States held title to the New Purchase; boundary extended north to Wabash River; reservations established