The County and City were named for the chief inhabitants, the Yumas. The Yumas were a combination of Indian tribes of the lower Colorado Region which consisted of the Quechans, the Cocopahs, and the Mohaves. These tribes were all bound by being members of one linguistic group. Yuma, rich in history of the old west had its glorious era. The mountain men, Fort Yuma soldiers, rivermen, railroaders, and the inmates of the infamous Territorial Prison make Yuma's history unforgettable.
Agriculture plays a dominant role in the Yuma County economy.
Over 219,000 acres were harvested in 1995 with 113,000 pen fed cattle. Military bases contribute substantially to the local economy with the Marine Corps Air Station and Yuma Proving Grounds located in the County. New and exciting light industry increases Yuma's economic diversification. The Mexican free-port of San Luis Rio Colorado is located 23 miles southwest of Yuma. For an industry interested in offshore manufacturing, or twin-plant operation, San Luis offers all facilities necessary for a modern manufacturing operation.