No written history of the area
that is now O'Fallon exists prior to 1673. Indians
may have inhabited the area as early as 8,000-12,000
B.C. The "Mississippian" culture of Native Americans
flourished in the area between 900 and 1350
B.C. After the decline of that culture there was a
small presence of Native Americans in this area.
The first recorded presence of
Europeans in St. Charles County occurred in June of 1673 when Father
Jacques Marquette and his companion, Louis Joliet, discovered the muddy
waters of the Missouri River flowing into the
Mississippi. The French claimed the territory that
the Missouri River drained into and by the 1770's a few French settlers
were living in St. Charles County, following the paths of the earlier
French fur traders. 
In 1770 France formally
surrendered possession of Upper Louisiana to Spain.
The Spanish continued the fur trading policies of the French and
established their own territorial government but Spain's formal control
of the area was weak. The territory was returned to
France for a short time from 1800 until the Louisiana Purchase when the
territory officially came under American control.
In the late 1790's
Anglo-Americans started crossing the Mississippi River into what is
today St. Charles County. Most of them came from
Kentucky, Tennessee and Virginia. The French
inhabitants of St. Charles County preferred the fur trade to farming
which, according to Meriwether Lewis, they regarded as a "degrading
occupation." The American settlers from Kentucky and
the other states of the upland south were much more interested in
agriculture. Daniel Boone, his wife, children,
adopted children, and other family members migrated to southern St.
Charles County where his oldest living son held a land grant from
1797. Daniel Boone was invited by the Spanish
government to migrate to this area they called New Spain along with a
number of other settlers with the promise of large tracts of land
should he encourage other families to migrate as well.