| |style=padding-left:10px|4 July 1848 - In the Treaty of Guadalupe-Hidalgo, [[Mexico Genealogy|Mexico]] ceded all of present day [[California, United States Genealogy|California]], [[Nevada Genealogy|Nevada]], and [[Utah Genealogy|Utah]], and parts of present day [[Arizona Genealogy|Arizona]], [[Colorado Genealogy|Colorado]], [[New Mexico Genealogy|New Mexico]], and [[Wyoming Genealogy|Wyoming]]. Part of the international boundary was in dispute.<ref>U.S. Stat., vol. 9, pp. 922-943</ref> <ref>Parry, Clive, ed. Consolidated Treaty Series. 231 vols. Dobbs Ferry, N.Y.: Oceana Publications, 1969–1981, 102: 29-59</ref> <ref>Van Zandt, Franklin K. Boundaries of the United States and the Several States. Geological Survey Professional Paper 909. Washington DC, 11, 28-29</ref> <ref>Walker, Henry P., and Don Bufkin. Historical Atlas of Arizona. 2nd ed. Norman: University of Oklahoma Press, 1986, 19, 20A</ref> The land south of the Gila River in present day Arizona was not ceded, it remained in control of Mexico. | | |style=padding-left:10px|4 July 1848 - In the Treaty of Guadalupe-Hidalgo, [[Mexico Genealogy|Mexico]] ceded all of present day [[California, United States Genealogy|California]], [[Nevada Genealogy|Nevada]], and [[Utah Genealogy|Utah]], and parts of present day [[Arizona Genealogy|Arizona]], [[Colorado, United States Genealogy|Colorado]], [[New Mexico Genealogy|New Mexico]], and [[Wyoming Genealogy|Wyoming]]. Part of the international boundary was in dispute.<ref>U.S. Stat., vol. 9, pp. 922-943</ref> <ref>Parry, Clive, ed. Consolidated Treaty Series. 231 vols. Dobbs Ferry, N.Y.: Oceana Publications, 1969–1981, 102: 29-59</ref> <ref>Van Zandt, Franklin K. Boundaries of the United States and the Several States. Geological Survey Professional Paper 909. Washington DC, 11, 28-29</ref> <ref>Walker, Henry P., and Don Bufkin. Historical Atlas of Arizona. 2nd ed. Norman: University of Oklahoma Press, 1986, 19, 20A</ref> The land south of the Gila River in present day Arizona was not ceded, it remained in control of Mexico. |