HistoricSiteMarkers
Early Republic

New Purchase Boundary (Treaty of St. Mary's)

Benton County, Benton County, Indiana

Marker Inscription

New Purchase Boundary (Treaty of St. Mary's) In October 1818, Purchasing Commissioners Lewis Cass, Benjamin Parke and Governor Jonathan Jennings acquired Indian claims on the land shown on this marker. About one-third of modern Indiana was involved in this transaction.

Erected by Indiana Historical Bureau

The Story

In October 1818, commissioners Lewis Cass and Benjamin Parke, with Governor Jonathan Jennings, negotiated the Treaty of St. Mary's, extinguishing Native land claims across a vast swath of central Indiana. The cession—the 'New Purchase'—opened roughly a third of the modern state to survey and settlement. The boundary it drew reshaped the map of frontier Indiana almost overnight.

Why it matters

The New Purchase was a pivotal act of dispossession and expansion, transferring Indigenous homelands to the United States and clearing the way for the rapid settlement of the Old Northwest.

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Related people

  • · Lewis Cass
  • · Benjamin Parke
  • · Jonathan Jennings

Related events

  • · Treaty of St. Mary's (1818)

Themes & tags

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