In 1539, Fray Marcos de Niza passed through what is now southeastern Arizona in search of the Seven Cities of Cibola.
In 1540, Francisco Vázquez de Coronado explored eastern Arizona also in search of the mythical cities.
In 1691, the Jesuit missionary, Father Eusebio Francisco Kino travelled through the Pimería Alta, establishing missions to convert the natives to Christianity.
The Spanish began giving large land grants in southeastern Arizona, which were turned into ranches (ranchos).
In 1821, the Treaty of Córdoba was signed, ending the Mexican War of Independence and giving Mexico control over New Spain.