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
History of St. Louis (1763–1803) Louisiana Purchase. The treaty was ratified by the U.S. Senate in November 1803, and the transfer of power from Spain was made official in St. Louis at a ceremony called Three Flags Day. On March 8, 1804, the flag of Spain was lowered at the government buildings in St. Louis and, according to local tradition, the flag of France was raised. On March 10, 1804, the French flag was replaced by the flag of the United States. History of St. Louis (1763–1803) The history of St. Louis, Missouri from 1763 to 1803 was marked by the transfer of French Louisiana