Montezuma Castle National Monument protects a well-preserved cliff dwelling located in Camp Verde, Arizona. The National Monument also protects and preserves the Castle A site, a contemporaneous dwelling site located near the cliff dwelling. The construction of the Montezuma Castle and Castle A sites are both attributed to the Southern Sinagua people, a pre-Columbian archaeological culture that may be closely related to several ancestral indigenous peoples of the southwestern United States. Archaeological evidence suggests that the dwelling was constructed as early as 1125 AD and occupied until as late as 1395 AD.

Many Native American communities trace their ancestry to groups of people that lived in or nearby the cliff dwelling. Archaeologists have defined these ancestral groups variously as Southern Sinagua, Hohokam and Hakataya. Archaeological labels do not constitute tribes as we understand them today and contemporary tribal communities may define their ancestry differently than archaeologists. These communities may oppose popular archaeological labels in favor of native-language terms or culturally specific social units.

Neither part of the monument's name is correct. When European-Americans first observed the ruins in the 1860s they named them for the famous Aztec emperor Montezuma in the mistaken belief that he had been connected to their construction (see also Montezuma mythology). Having no connections to the Aztecs, the Montezuma Castle was given that name due to the fact that the public had an image of the Aztecs building many archaeological sites in the American Southwest . In fact, the dwelling was depopulated more than 40 years before Montezuma was born, and was not a "castle" in the traditional sense, but instead may have functioned more like a "prehistoric high rise apartment complex". Many tribal groups throughout the Southwest have specific place names for the cliff dwelling in their respective languages.

Montezuma Castle is situated about 90 feet (27 m) up a sheer limestone cliff, facing the adjacent Beaver Creek, which drains into the perennial Verde River just north of Camp Verde. It is one of the best-preserved cliff dwellings in North America, in part because of its ideal placement in a natural alcove that protects it from exposure to the elements. The precariousness of the dwelling's location and its immense scale of floor space across five stories suggest that the Sinagua were daring builders and skilled engineers. Access into the structure was most likely permitted by a series of portable ladders, which made it difficult for enemies to penetrate the natural defense of the vertical barrier.

The walls of Montezuma Castle are examples of stone-and-mortar masonry, constructed almost entirely from chunks of limestone found at the base of the cliff, as well as locally acquired mud mortar. Studies have shown that several different types of mud mortar were especially engineered for specific purposes like durability, strength and color. The ceilings of the rooms also incorporated sectioned timbers as a kind of roof thatching, obtained primarily from the Arizona sycamore, a large hardwood tree native to the Verde Valley. Other wood used for roofing includes Ash, Alder, Ponderosa Pine, Douglas Fir and Pinyon Pine.

Evidence of permanent masonry dwellings like those at Montezuma Castle begins to appear in the archaeological record of Arizona's Verde Valley about 1050 AD. Archaeologists recognize the earliest cultural traits of the Southern Sinagua-consisting of a recognizable set of objects and architecture-as early as 700 AD.

The area was briefly depopulated due to the eruption of Sunset Crater Volcano, about 60 miles (97 km) to the north, in the mid-11th century. Although the short-term impact may have been destructive, nutrient-rich sediment deposited by the volcano may have aided more expansive agriculture in later decades. During the interim, the Sinagua lived in the surrounding highlands and sustained themselves on small-scale agriculture dependent on rain. After 1125, the Sinagua resettled the Verde Valley, using the reliable watershed of the Verde River alongside irrigation systems left by previous inhabitants, perhaps including Hohokam peoples, to support more widespread farming.

The region's population likely peaked around 1300 AD, with the Castle housing no more than 30 people in at least 20 rooms. Radiocarbon dates from multiple construction beams at the Montezuma Castle suggest that the cliff dwelling was constructed between 1125 AD to 1173 AD with remodeling and additions in the last decades of the 13th century. A neighboring segment of the same cliff wall suggests there was an even larger dwelling ("Castle A") around the same time. Castle A had an estimated 45 rooms and would have had a large number of inhabitants that contributed greatly to the population of the area. Castle A is in a relatively poor state of preservation with remaining architecture consisting mostly of stone foundations. The site's excavation in 1933 revealed many artifacts and helped archaeologists to develop a more detailed understanding of life in the area. Archaeological evidence and Native American oral histories suggest the Castle A site was destroyed by fire sometime between 1375 AD and 1395 AD and both dwellings were depopulated shortly thereafter.