Yuma Crossing
Immediately after the Mexican–American War in 1848, the U.S. Army built Fort Yuma here to protect travelers from Indians raiding the area. It was the center point of conflict in the Yuma War of 1850–53. From 1864–1890, the fort and nearby facilities was the main army base to support the US Army's efforts to control the Indians throughout the greater southwest.
The Church of Jesus Christ of Latter-day Saints
By 1857, tensions had again escalated between Mormons and other Americans, largely as a result of accusations involving polygamy and the theocratic rule of the Utah Territory by Young. The Utah Mormon War ensued from 1857 to 1858, which resulted in the relatively peaceful invasion of Utah by the United States Army, after which Young agreed to step down from power and be replaced by a non-Mormon territorial governor, Alfred Cumming. Nevertheless, the LDS Church still wielded significant political power in the Utah Territory.