was captured and executed. The retribution of the Mexicans against the Opata after the defeat of the French occupation resulted in the loss of nearly all of their remaining lands and the end of their resistance to Mexican rule. 20th century In 1902, American anthropologist Ales Hrdlicka, estimated the number of full-blood Opatas at 500 to 600. Another anthropologist, Carl Lumholtz, commented that the Opatas had “lost their language, religion, and traditions, dress like the Mexicans, and in appearance are in no way distinguishable from the laboring class of Mexico with which they are thoroughly merged through frequent intermarriage.” Population Population estimates for Opatería at the time of Spanish contact range from 20,000 to 70,000, with most estimates nearer the higher figure. The Opatas were the most numerous of the several indigenous groups in the state of Sonora, and the river valleys of their territory were densely populated with their permanent villages. Disease, war, and famine reduced the aboriginal population of Opatería to 6,000 by 1764. Today, there are no known full-blooded Opatas left, but mestizo descendants still make up the majority population of traditional Opata territory. Many Opata descendants reside in other parts of Sonora, greater Mexico, and the southwestern United States, particularly in Arizona, where their ancestors migrated to work in agriculture and mining. Culture Settlement pattern and livelihood At the time of first contact with the Spanish, the Opata may have been the most numerous and culturally complex people living in Oasis America, comprising the desert regions of northern Mexico and the southwestern United States. The towns of the Opata were found in the broad valleys of the five north-south trending rivers of northern and eastern Sonora. The rivers, west to east, are the San Miguel, Sonora, Moctezuma, and the two upper tributaries of the Yaqui, the Bavispe and the Arcos. The Opata were not members of a single political entity, but rather organized into a number of “statelets” – several of which may have also been populated by their neighbors to the south, the Pima Bajo. The statelets were characterized by a ruling class, slavery, irrigation agriculture, and emphasis on trade. They featured a central town, functioning as the seat of government, of at least 200 two and three-story adobe houses and a population of six per house or 1,200 or more. In the countryside for several miles in every direction from the central town were