Answer:
When Americans won their independence from the British in 1783, they also acquired the lands south east of Canada and east of the Mississippi River.
Step-by-step explanation:
The treaty of Paris officially proclaimed independence of United States. Besides independence newly formed state obtained territories that were once part of Britain. Therefore, all the territories south of Canada which was in the hands of Britain was in the hands of US.
On the other side Mississippi River was a newly established boundary between US and France.