The area of Union Township was originally under the authority of the New Bourbon District, which was one of two districts formed by the French colonial administration of Upper Louisiana (New France). Authority passed from French to Spanish colonial administration when the colony was handed over to Spain in 1762. The French colonials in Ste. Genevieve were continuously harassed by Osage Indians to the south. Looking to stop the harassment and raids, the Spanish authorities in the 1790s invited Shawnee and Delaware Indians from Indiana and Ohio to immigrate and settle in the area around Apple Creek to act as a buffer against Osage raids. The Shawnee and Delaware established a number of villages around Apple Creek, with Le Grand Village Sauvage or "Big Village" as it was known to the Americans, being one of the largest. American harassment and encroachment on Shawnee and Delaware lands caused tensions and the eventual removal of the Shawnee and Delaware from the region.
