[1] After the Marcos de Niza expedition in south-eastern Arizona in 1539, Coronado also explored several regions of the present state in 1540–1542, while searching for Cíbola.
Ten Spaniards members of the expeditionary team settled in the region, although the mission did not prosper.
In 1736 silver mines were discovered in the region, prompting the arrival of possibly 100 traders and miners.
In addition, the Pima people frequently attacked the Spanish communities, causing riots and murders (100 settlers were murdered), as well as many other problems – they burned the settlers' land, poisoned the wells, etc.
So only a small settler community remained in Arizona, including the farmer José Romo de Vivar.
The U.S. won the Mexican–American War (1846–1848) and Mexico ceded to the U.S. the northern 70% of modern-day Arizona through the Treaty of Guadalupe Hidalgo (1848).
Arizona was projected to become a minority-majority state by the year 2015 if population growth trends continued.
As of 2010, 21% (1,202,638) of Arizona residents age 5 and older spoke Spanish at home as a primary language.
[10] The state (like its southwestern neighbors) has had close linguistic and cultural ties with Mexico.
The area of the former Gadsden Purchase contained a majority of Spanish-speakers until the 1940s, although the Tucson area had a higher ratio of anglophones (including Mexican Americans who were fluent in English); the continuous arrival of Mexican settlers increases the number of Spanish speakers.