Early view of St. Louis
The United States and France signed the Louisiana Purchase Treaty on April 30, 1803. As part of the treaty, the town of St. Louis in what is now Missouri was officially transferred to the United States less than a year later. This map from that period shows a small town of 180 homes nestled under a bluff along the river. The small, four-pointed star on the bluff is a fort completed in 1764.
National Archives, Office of the Chief of the Engineers