A region conceived as "the Indian country" was specified in 1825 as all the land lying west of the Mississippi. Eventually, the Indian country or the Indian Territory would encompass the present states of Oklahoma, Kansas, Nebraska, and part of Iowa.
Farewell Address by Washington--this address urged the nation to avoid alliances and getting involved in affairs not our own. This set the tone for isolationism.
Monroe Doctrine--this foreign policy stated the US would protect the Western Hemisphere from European involvement and implied the US would stay out of European affairs.
The Treaty of Versailles and League of Nations would involve the US in world affairs and bring European issues to the doorstep of the US.
50 years, 5 months and 11 days
Answer: The war officially ended with the February 2, 1848, signing in Mexico of the Treaty of Guadalupe Hidalgo. Mexico gave up all claims to Texas and recognized the Rio Grande as America's southern boundary.
Explanation: Hope this helped!! :D