Yuma County was one of the original four counties designated by the First Territorial Legislature. Until 1983, when voters decided to split it into La Paz County in the north and a new Yuma County in the south, it maintained its original boundaries.
In 1540, just 48 years after Columbus discovered the New World, 18 years after the conquest of Mexico by Cortez and 67 years before the settlement of Jamestown, Hemando de Alarcon visited the site of what is now the city of Yuma. He was the first European to set foot in the area and to recognize the best natural crossing of the Colorado River.
From the 1850s through the 1870s, steamboats on the Colorado River transported passengers and goods to mines, ranches and military outposts in the area, serving the ports of Yuma, Laguna, Castle Dome, Nortonís Landing, Ehrenberg, Aubry, Ft. Mohave and Hardyville.
For many years, Yuma served as the gateway to the new western territory of California. In 1870, the Southern Pacific Railroad bridged the river, and Yuma became a hub for the railroad and was selected as the county seat.
Much of Yuma Countyís 5,519 square miles is desert land accented by rugged mountains. The valley regions, however, contain an abundance of arable land, which is irrigated with Colorado River water. Agriculture, tourism, military and government are the countyís principal industries. During the winter months, the population grows considerably with pad-time residents. All of Yuma County is an Enterprise Zone.
The U.S. Bureau of Land Management accounts for 42 percent of land ownership; Indian reservations, less than 0.5 percent; the state of Arizona, 5 percent; individual or corporate, 13 percent; and other public lands, 40 percent.
From: Arizona-A Review of its Resources Published 1891.
YUMA County is in the extreme southwest of the Territory. Its western boundary is the great Colorado River; its northern, Mohave County; its eastern, Maricopa and part of Pima County; and its southern, Sonora. It contains about 10,180 square miles. The only really fertile portion of the county is that through which the Gila River flows. The rest is arid and treeless and destitute of water, except a few stretches along the Colorado River. In the northeast portion there are some very fine grass lands. Yuma, the county seat, lies on the Colorado just below where the Gila joins it. A mission was established there by the Jesuit Fathers in 1771, but the Indians soon laid it in ruins. A ferry was established there in 1849 to accommodate the crowds who were flocking to the California gold mines over the Southern route, but that scheme, too, was frustrated by the raids of the Apaches. A second attempt, made the following year, to set the ferry running, also resulted in failure. In 1852 Fort Yuma was established by Colonels Heintzelman Stevenson, and the ferry again started. It was maintained by the protection afforded by the fort until the Southern Pacific Railroad Company spanned the river with a bridge, when, of course, the usefulness of the ferry ceased. The town did quite an amount of shipping of freight to Tucson and the various military forts of the Territory for a time, but that business stopped when the railway came through, and now Yuma has to depend on the comparatively limited trade with the surrounding country. Two of its most important institutions, at the present time, are the Territorial prison and the Arizona Sentinel, and both are doing excellent work -- though on entirely different lines. The old fort has been abandoned to decay, there being no longer any necessity for its maintenance by the Government