Many Americans in the early 1800s believed that America was to contain all of the North American continent. This belief was called "Manifest Destiny." The term came from a New York newspaper editorial of December 27, 1845, which stated that the nation's manifest destiny was "to over spread and to possess" the whole continent, to develop liberty and self-government to all. In the eyes of the Americans, it was his or her goal to expand their territory from coast to coast.
In 1803 Thomas Jefferson was President of the US and the Mississippi River was basically western border of the US. Napoleon Bonaparte controlled the huge piece of land west of the Mississippi River. This land stretched from the Mississippi River all the way to the Rocky Mountains and was called the Louisiana Territory. Napoleon in the middle of a war with Great Britain and needed money to finance the war. …