Southwestern United States
geographical region of the USA

The Southwestern United States, also known as the American Southwest or simply the Southwest, is a geographic and cultural region of the United States that includes Arizona and New Mexico, along with adjacent portions of California, Colorado, Nevada, Oklahoma, Texas, and Utah. The largest cities by metropolitan area are Phoenix, Las Vegas, El Paso, Albuquerque, and Tucson. Before 1848, in the historical region of Santa Fe de Nuevo México as well as parts of Alta California and Coahuila y Tejas, settlement was almost non-existent outside of New Mexico's pueblos and Spanish or Mexican municipalities. Much of the area had been a part of New Spain and Mexico until the United States acquired the area through the Treaty of Guadalupe Hidalgo in 1848 and the smaller Gadsden Purchase in 1854.
While the region's boundaries are not officially defined, there have been attempts to do so. One such definition is from the Mojave Desert in California in the west (117° west longitude) to Carlsbad, New Mexico, in the east (104° west longitude); another says that it extends from the Mexico–United States border in the south to the southern areas of Colorado, Utah, and Nevada in the north (39° north latitude). In another definition, the core Southwestern U.S. includes only the states of Arizona and New Mexico; others focus on the land within the old Spanish and Mexican borders of the Nuevo México Province or the later American New Mexico Territory.
Distinct elements of the Western lifestyle thrive in the region, such as Western wear and Southwestern cuisines, including Native American, New Mexican, and Tex-Mex, or various genres of Western music like Indigenous, New Mexico, Bluegrass, and Tejano music styles. Likewise with the sought-after Southwestern architectural styles in the region inspired by blending Pueblo and Territorial styles, with Mediterranean Revival, Spanish Colonial architecture, Mission Revival architecture, Pueblo Deco, and Ranch-style houses in the form of the amalgamated Pueblo Revival and Territorial Revival architectures. This is due to the region's caballero heritage of the Native American (especially Apache, Pueblo, and Navajo), Hispano, Mexican American, and frontier cowboy.
Begin with the source’s own compact description: “Southwestern United States” is geographical region of the USA. The dossier treats that line as a proposition to test through Southwestern, United and States, not as a finished interpretation.
Why this record matters
The phrase “geographical region of the USA” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 13, 2026. The linked authority identifier is Q858847. VIAF identifies the subject as 315128196. The Library of Congress control number is sh85125686. Authority coordinates are 37.000, -111.200. None of the 3 selected statements returned an explicit reference. The first chronological checks are 1848 and 1854.
Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
How to read it
Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.
- Subject orientation
- Search vocabulary
- Locating named sources
The closest primary source, responsible institution and strongest cited specialist reference.
Three-step research path
- Establish the record: confirm the title “Southwestern United States”, its source revision and the description used here.
- Expand the search: follow Southwestern United States primary sources, Southwestern United States archive and Southwestern research across catalogues and specialist indexes.
- Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.
Questions for further research
- Which source most directly establishes the central claim about “Southwestern United States”?
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- Which cited source is closest to the event, object or claim?
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This entry incorporates text from “Southwestern United States” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.