Yuma War
The Yuma War was the name given to a series of United States military operations conducted in southern California and what is today southwestern Arizona from 1850 to 1853. The Yumans were the primary opponent of the United States Army, though engagements were fought between the Americans and other native groups in the region. Conflict generally took the form of guerrilla warfare, and, over the course of three years, the army engaged in pursuing unfriendly natives, protecting American settlers crossing the Colorado River and preventing conflict between the native tribes. A peace treaty in summer of 1853 was signed, ending hostilities between the Yuma and the United States, but it sparked a short war between the Yuma and the Cocopah. During the conflict, the historic Fort Yuma was constructed and became an important outpost on the frontier.
Yuma Expedition
After reconnoitering his route, Heintzelman marched out of San Diego on 3 October 1850 with three companies of the 2nd Infantry Regiment with another infantry company establishing a depot at Vallecitos. He then sent a small party in advance digging wells in the desert between Vallecitos and the Colorado River. He reached Vallecitos 3 November and the Yuma Crossing on 27 November, a third company arriving a few days later. Camp Yuma was established with the tents protected from sun and wind by brush and reed fences and arbors. A garden and vinyard were started near the river. The Quechan living in the vicinity of the camp were quiet and friendly.