Yuma is a city in and the county seat of Yuma County, Arizona, United States. It is located in the southwestern corner of the state, and the population of the city was 93,064 at the 2010 census, up from the 2000 census population of 77,515.
Yuma is the principal city of the Yuma, AZ Metropolitan Statistical Area, which consists of Yuma County. According to the United States Census Bureau, the 2013 estimated population of the Yuma MSA is 201,201, though more than 85,000 retirees make Yuma their winter residence.
The area's first settlers were Native American tribes whose descendants now occupy the Cocopah and Quechan reservations. In 1540, expeditions under Hernando de Alarcon and Melchior Diaz visited the area and immediately saw the natural crossing of the Colorado River as an ideal spot for a city, as the Colorado River narrows to slightly under 1,000 feet wide in one small point. Later military expeditions that crossed the Colorado River at the Yuma Crossing include Juan Bautista de Anza (1774), the Mormon Battalion (1848) and the California Column (1862).
During and after the California Gold Rush to the late 1870s, the Yuma Crossing was known for its ferry crossings for the Southern Immigrant Trail, the gateway to California, as it was one of the few natural spots where travelers could cross the otherwise very wide Colorado River.
Following the establishment of Fort Yuma, two towns sprang up 1 mile down river. The one on the California side was called Jaeger City, named after the owner of Jaeger's Ferry that crossed the river there. It was for a time the larger of the two, with the Butterfield Overland Mail office and station, two blacksmiths, a hotel, two stores, and other dwellings. The other called Colorado City, a land speculation by Charles Poston and site of the custom house, sprang up on the south side of the Colorado River in what is now Arizona, but at that time was just north of the border between Sonora, Mexico and California. After the Gadsden Purchase it bordered on the Territory of New Mexico, that became the Territory of Arizona in 1863. The Colorado City site at the time was duly registered in San Diego, demonstrating that both banks of the Colorado River just below its confluence with the Gila were recognized as being within the jurisdiction of California. The county of San Diego collected taxes from there for many years. From 1853 a smaller settlement, Arizona City, grew up on the high ground across from the fort and was organized under the name of its post office in 1858. It had adobe dwellings, two stores and two saloons. Colorado City and Jaeger City were almost completely destroyed by the Great Flood of 1862 and had to be rebuilt on higher ground and Colorado City became part of Arizona City. It took the name Yuma in 1873.
From 1854, Colorado City, was the major steamboat stop on the way up and down the Colorado River. The steamboats transported passengers and equipment for the various mines and military outposts along the Colorado and was the terminus of wagon traffic up the Gila River into New Mexico Territory. They offloaded the cargo from ships at the mouth of the Colorado River at Robinson's Landing and from 1864 at Port Isabel. From 1864, the Yuma Quartermaster Depot, today a state historic park, supplied all forts in present-day Arizona, as well as large parts of Colorado and New Mexico. After Arizona became a separate territory, Yuma became the county seat for the area in 1864.
The Southern Pacific Railroad bridged the river in 1877, and acquired George Alonzo Johnson's Colorado Steam Navigation Company, the only steamboat company on the river. Yuma became the head of navigation on the river, ending the need for Port Isabel, which was abandoned in 1879.