A

The Mexican state of Sonora and the Sonoran Desert overlap to a great extent, but not entirely. About half of Sonora state, mostly the western and southern parts, lies in the Sonoran desert while the other half, mostly the eastern is plains and mountains. And about half of the Sonoran desert is in Sonora state with much of the rest in Arizona but some in California and Baja California. Almost all of the desert would be in Mexico and thus in Sonora if it had not been for the Gadsden purchase of 1853. After the Mexican-American war of 1846, the treaty of Guadalupe-Hildalgo that ended it set the border along a line mostly defined by the Gila and Rio Grande Rivers. As far as Arizona is concerned, that meant that the border between 1846 and 1853 left Tucson, Casa Grandes, Saguaro National Park, Organ Pipe National Monument, and the O'odham and Apache Indian reservations in Mexico. Soon surveys for a proposed east-west American railroad showed that the best route would pass pretty much along what today is US Interstates 8 and 10, i.e. include territory with Tucson and all the above named places. James Gadsden was sent to Mexico City and made an offer that couldn't be refused. The USA added 29,600 sq miles to what was then the New Mexico territory and was later split into the states of New Mexico and Arizona.

Although it was a land grab, things aren't quite as bad as they seem. At the time both Mexicans and Americans largely considered the land worthless, for they were interested mostly in farming, ranching, and mining, and the Gadsden Territory lands appeared uninviting for all three. The Arizona part is 2/3 desert and the other 1/3 is mountainous territory. In our driving south of Altar, we saw that the lands were much greener than north of it. Whereas in most of Southern Arizona it would either be impractical to graze cattle or the number per acre would be very low, the lands south of Altar looked as if they could support many more. From a 19th century perspective it is clear that Mexico kept the far better lands.

The area of the Gadsden purchase was then inhabited primarily by Apaches, disliked by European settlers and other indians, such as the Pima, and Papagos, who were the subject of incessant Apache raids. The original treaty of Guadalupe-Hildago required the USA to protect Mexicans from cross border raids. By getting more of Indian lands in the USA this made it easier to carry out American obligations. It is also interesting to note that many of the O'odham later moved from their traditional territories that remained under Mexican control to the territories under American control because they felt that would make it easier for them to preserve their traditional ways.

The truncated Sonora is still the second largest state in Mexico with a territory of 180,833 sq. km (69,820 sq mi.). This makes it much smaller than Arizona (295,274 sq km, 114,006sq mi), smaller than Britain (229,980 sq km, 88,795 sq mi), but bigger than England (130,410 sq km, 50,352 sq mi) or Scotland (78,790 sq km, 30,420 sq mi). Its population has recently been growing very fast, now at about 2.3 million. Early in the 20th century it was below 500,000. Its literacy levels and general standard of living rank among the highest in Mexico. We find this reflected in local prices: they aren't often much below those in the USA. The undoubted reason is the high number of maquiladora plants here and the cross border exchanges. We seem to run every day into somebody who has one parent living in the USA and another in Mexico: examples: Hotel keep in Sonoyta 15 years old, goes to school in Ajo, Arizona. High school student in Hermosillo, wants to study in San Francisco where her American father lives. Met Hermosillo museum director; he is Belgium, has lived here 6 years, in charge of museum 2 years.

Given that the names of desert and state are the same you might thing that they would have the same etymology. But our encyclopedias tell a different story (or stories) Accordings to the Encarta encyclopedia the desert probably takes its name from the Tohono O'Odham (Papago) language term Sonota, which means "place of plants." And according to the Britannica, the state takes its name from the sound made by marble pieces taken from mines that were important to the economy in the early days of colonization.