Final answer:
Following the Louisiana Purchase, non-US citizens in the territory were not immediately granted citizenship rights or political representation; treatment and rights were shaped over time through treaties, amendments, and societal changes.
Step-by-step explanation:
When the United States acquired the Louisiana Territory through the Louisiana Purchase in 1803, it gained ownership over an immense area that effectively doubled the size of the country. However, this expansion did not immediately grant citizenship rights or political representation to the non-US citizens living in the newly acquired territory. The Fourteenth Amendment, ratified much later in 1868, established citizenship for 'all persons born or naturalized in the United States,' but this was a post-Civil War development and did not apply to the time immediately following the Louisiana Purchase. The historical context suggests that while the United States was interested in the land for westward expansion and economic exploitation, it did not immediately address or acknowledge the rights and citizenship status of the residents in the newly acquired territories, be it the European descendants or the indigenous populations. The complex interplay between expansionism, land acquisition, and the rights of the existing residents was a gradual process, influenced by various treaties, amendments, and societal changes over time.