 They wanted to expel the remaining Indians from the entire Southeast east of the Mississippi River.After the transfer of the vast Louisiana Territory from Spain to France at the end of the 18th century, and the subsequent purchase of the region by the United States in 1803, Spanish East and West Florida were surrounded by American Southern states and territories.Anglo-American settlement of West Florida increased and the Spanish, busy with growing rebellions throughout Mexico and South America, were not able to focus on fortifying the region.