The Cocopahs traditionally maintained little political leadership. They lived in small settlements, or rancherias, of ten to twelve families. Society was organized into clans, with each clan having a leader. Other quasi officials included dance and war leaders and funeral orators. Leadership was generally determined by experience, ability, and, as with everything else, dreams.
Originally concentrated in nine rancherias, the Cocopahs built two different types of homes. In winter they built conical, partially excavated (later four-post rectangular) structures, covering the walls of sticks with earth. In summer they built oval-domed, brush-covered huts. They also used a circular, unroofed ramada for dwelling and/or cooking and small granaries with elevated floors for storing food.
Corn, beans, black-eyed peas, pumpkins, and later melons were planted, usually in July. Gathered food, such as the seeds of wild saltgrass, roots, fruits, eggs, and especially mesquite, were also important, as was fish (such as mullet and bass) from the river and the Gulf of California. Wild game included deer, boar, and smaller animals. Much of the food was dried and stored for the winter. In general, the women gathered and cooked food, and the men hunted.
The Cocopahs planted seeds in holes rather than plowed rows in order to preserve topsoil. They used pottery (jars, seed-toasting trays), crude baskets, fire drills, vegetable-fiber fishing nets, clubs and bow and arrow for warfare, stone and wooden mortars, and stone and clamshell tools. Their musical instruments included a scraped and drummed basket, gourd rattles, and cane flutes and whistles. They also used small earthen dikes for irrigation.
Warfare united the Cocopahs. They observed formalized war patterns and respected special war leaders. They prepared for war by dreaming, fasting, and painting their bodies and underwent purification rituals upon their return. Traditional enemies included the Mojave and the Quechan; allied peoples included the O'odham, Pee-Posh, and Pai. Their weapons were the war club, bow and arrow, lance, and deerskin shield.
By 1540 the Mojave and Quechan Indians had forced them down the Colorado River, to a place where they farmed 50,000 acres of delta land, made rich by the annual spring floods. The Cocopahs encountered Spanish soldiers and travelers during the mid-sixteenth century but remained in place and relatively unaffected by contact with the Europeans until U.S. dams stopped the Colorado from flooding in the late nineteenth century.
In 1853, the Gadsden Treaty separated the four bands of Cocopahs: Two remained in Mexico, and two moved north near Somerton, Arizona. By the mid-1800s, with the cessation of warfare with their ancient enemies, the Quechans, the Cocopahs lost a certain sense of purpose. A generation of men obtained employment as river pilots and navigators along the Colorado River, whetting their appetite for American goods and foods. Riverboat traffic ended when the railroad reached Yuma in 1877. In 1905, an accidental diversion of the Colorado River (the Salton Sea debacle) led to the Cocopahs' final displacement. Lacking strong political, religious, or social leadership, they quickly fell further into disintegration and impoverishment.
Thanks mainly to the work of Frank Tehanna, the U.S. government established a reservation in 1917 for the Cocopahs and some Quechans and Pee-Posh. The government then almost completely abandoned them for the next sixty years. By the end of World War II, fewer than sixty Cocopahs remained on the desolate reservation; the rest lived elsewhere, generally in even worse poverty. In the 1960s, the tribe organized and won from the government electricity and improved housing, building their first tribal building and rewriting their constitution.
In 1986, the tribe received an additional 615 acres, now known as the North Reservation. In the 1970s and 1980s, the tribe made improvements in education as well as other social and cultural programs. That period also witnessed a revival of crafts such as beadwork and the development of fine arts.