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 France was returned to the king. Louis XV saw no value in Louisiana, and in order to bring about an end to the Seven Years' War, he transferred Louisiana to his cousin Charles III of Spain in 1763. Louisiana remained under the control of Spain until it was demanded to be turned over to France by Napoleon. Although Louisiana was property of France by the Third Treaty of San Ildefonso in 1800, Louisiana continued to be administered by Spain until the Louisiana Purchase in 1803. Following the Louisiana purchase, the population of the subsequently divided territory that contained most of present-day