How Tennessee Became the "Volunteer" State

When Tennessean James K. Polk was elected to the Presidency in 1844, he followed through on his campaign promise to annex the Independent Republic of Texas into the United States.
Although officially recognized by England and France as well as the U.S., Mexico disputed Texas sovereignty and immediately withdrew her representatives from Washington, D.C.
President Polk dispatched General Zachary Taylor to advance the American Army to the Rio Grande across from the City of Matamoros.
Polk , however, was a master at the art of intrigue and always hedged his bets with emissaries trying to negotiate peaceful settlements. His forays into Mexican- held California and New Mexico laid the groundwork for American expansion to the coast of the Pacific. In the midst of the brewing problems in Mexico, he led a successful diplomatic assault on Great Britain’s claims to Oregon territory and purchased the property to prevent the British from laying claim to the California territories, which he desperately wanted in order to establish a "Golden Gate" trade with the emerging Asian nations.
The Mexican Government, however, recognized the expansionist policies and refused to see Polk’s envoy sent to negotiate a peaceful settlement. The action prompted Mexico to take an aggressive stand against the American soldiers on the Rio Grande.What would follow would affect not only Texas and the United States, but would forever change the way people looked at the state of Tennessee.

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