History of St. Louis (1763–1803) History of St. Louis (1763–1803) The history of St. Louis, Missouri from 1763 to 1803 was marked by the transfer of French Louisiana to Spanish control, the founding of the city of St. Louis, its slow growth and role in the American Revolution under the rule of the Spanish, the transfer of the area to American control in the Louisiana Purchase, and its steady growth and prominence since then. In mid-1763, French Governor Jean-Jacques Blaise d'Abbadie granted a trade monopoly over the west upper Mississippi region to Gilbert Antoine de St. Maxent, a New Orleans merchant. Maxent quickly engaged the
Mississippi River from Napoleon of France, Spain ceded an undefined portion of West Florida to France. When France then sold the Louisiana Territory to the U.S. in 1803, a dispute arose again between Spain and the U.S. on which parts of West Florida exactly had Spain ceded to France, which would in turn decide which parts of West Florida were now U.S. property versus Spanish property. These aspirations ended when Spain was pressured into signing Pinckney's Treaty in 1795. France reacquired 'Louisiana' from Spain in the secret Treaty of San Ildefonso in 1800. The United States then secured effective control of the