Manifest Destiny

Several factors combined to produce the expansionist movement known as the Manifest Destiny. Chief among these was the seemingly habitual ambition, nurtured by the restlessness of the American pioneer spirit, to move on to new land. Expanding the United States to the Pacific involved risks, for it meant taking the land claimed or settled by other peoples. The United States, with limited military power, had to weigh carefully the possibility of hostilities with Native Americans …

…Ohio, then to Missouri, and then to Illinois. At Nauvoo, Illinois, they built a thriving community of 20,000 people. In 1844, howver, Joseph Smith was jailed for ordering the destruction of a printing press that belonged to people who disagreed with him. An angry mob then killed Smith and his brother. Brigham Young, the new leader, believingthat no safe refuge could be found in th United States, sought an isolated haven in territory that belonged to Mexico.