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
New Spain Spanish Conspiracy, hoped to gain greater control of Louisiana and all of the west. These hopes ended when Spain was pressured into signing Pinckney's Treaty in 1795. France re-acquired Louisiana from Spain in the secret Treaty of San Ildefonso in 1800. The United States bought the territory from France in the Louisiana Purchase of 1803. New Spain claimed the entire west coast of North America and therefore considered the Russian fur trading activity in Alaska, which began in the middle to late 18th century, an encroachment and threat. Likewise, the exploration of the northwest coast by Captain James Cook of