What states were purchased in The Louisiana Purchase?
The Louisiana Purchase included the Mississippi and Missouri valleys west of the Mississippi. This included the states of Arkansas, Missouri, Iowa, Oklahoma, and Kansas, and parts of Minnesota, North Dakota, South Dakota, New Mexico, Montana, Wyoming, Colorado, and Louisiana (the areas east of the Mississippi, and north of New Orleans, were part of Florida).
It also included lands which are now part of southern Canada.
The USA grew much much larger with the Louisiana purchase because what you know of as the 'Plains states' were all part of that purchase. Practically all the land that is part of the USA from Saint Louis through the Rockies was all purchased at that time. More The size of the United States doubled with the Louisiana Purchase. There is a link below for more information.
Present states that lie within the land from the Louisiana Purchase include parts of Montana, Wyoming, Colorado, New Mexico, Texas, Louisiana, Minnesota, and North Dakota. In addition. the whole state of Oklahoma, Arkansas, Missouri, Kansas, Nebraska, Iowa, and South Dakota are included in the land purchased at that time.