Soldiers were established west of the Mississippi to protect emigrants following the Oregon Trail. They served as escorts and eventually established a network of forts and posts. Soldiers were to provide protection from Indian tribes that might take advantage of unsuspecting travelers; they also protected Indians from the lawlessness of some Euro-Americans.

The earliest settlements of westward expansion were the forts. They were centers of trade and commerce and brought growth, stability, and trade. The soldiers helped to build roads and later string telegraph lines.

A soldier's life was not glamorous, perhaps a fact learned too late after men enlisted. Some men romanticized the life while others wished to escape from a lackluster career or an unhappy home life. Other soldiers came to the West from the Civil War battlefields. Many were recent European immigrants, and after the Civil War, former slaves. A soldier's life would entail wearing wool uniforms and living in crowded, unsanitary barracks. Often the men had only beef, beans, stew, or bacon to eat. They averaged around $13.00 per month in wages.

The Buffalo Soldier came to the West for a new way of life. The African-Americans who served in the West were a new sight for Indians and the name "Buffalo Soldier" was coined and perceived as complimentary. Buffalo Soldiers served under white officers in the Ninth and Tenth Cavalry Regiments and the Twenty-Fourth and Twenty-Fifth Regiments. Eighteen Buffalo Soldiers were awarded the Congressional Medal of Honor.

The Indian Wars were a result of a clash of cultures that led to many short, bloody battles. There were rare stories of unprovoked American Indian attacks on innocent families that brought about outrage by the rest of the country. These violent acts led to the United States military retaliating against the tribe responsible.

"There is not a tribe of Indians on the Great plains or in the Mountains...but which is warring on the whites. The first demand of the Indian is that the white man shall not come into his country: shall not kill or drive off the game upon which his subsistence depends: and shall not disposses him of his lands." The mass migration of Euro-Americans into the west was monitored by soldiers who prevented squatters from encroaching upon American Indian land. As the overlanders were migrating west they cut a path that divided the great buffalo herds of the Plains. The buffalo was the life source for the Plains Indians and their hunting of these animals became disrupted. The tribes may have been helpful initially to the overlanders but hospitable feelings turned to resentment as their way of life began to decline.

The government began establishing treaties with the American Indians and giving them rations of food, clothing and farm implements to allow the pioneers to continue to pass through their territory. At first the tribes were cooperative. In the Pacific Northwest the military was called in to provide a buffer between the settlers and the American Indians. By the 1860s, mounting pressure sparked battles on the Plains. The sentiment of many whites was stated by Philip Sheridan when he said that, "The only good Indian is a dead Indian."

The American Indians' land was taken from them, they were forced to live on reservations and they did not have the manpower to fight back. Many reservations were on worthless land. They could not farm or raise stock on much of the land. Most devastating for their culture was the lack of hunting on the reservations.

By the time of the Civil War, the flow of emigrants slowed, but revived afterward with the completion of the transcontinental railroad in 1869.