The United States of America known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U. S. is the third most populous country. The capital is Washington, D. C. and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico; the State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean; the U. S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The diverse geography and wildlife of the United States make it one of the world's 17 megadiverse countries.
Paleo-Indians migrated from Siberia to the North American mainland at least 12,000 years ago. European colonization began in the 16th century; the United States emerged from the thirteen British colonies established along the East Coast. Numerous disputes between Great Britain and the colonies following the French and Indian War led to the American Revolution, which began in 1775, the subsequent Declaration of Independence in 1776; the war ended in 1783 with the United States becoming the first country to gain independence from a European power. The current constitution was adopted in 1788, with the first ten amendments, collectively named the Bill of Rights, being ratified in 1791 to guarantee many fundamental civil liberties; the United States embarked on a vigorous expansion across North America throughout the 19th century, acquiring new territories, displacing Native American tribes, admitting new states until it spanned the continent by 1848. During the second half of the 19th century, the Civil War led to the abolition of slavery.
By the end of the century, the United States had extended into the Pacific Ocean, its economy, driven in large part by the Industrial Revolution, began to soar. The Spanish–American War and World War I confirmed the country's status as a global military power; the United States emerged from World War II as a global superpower, the first country to develop nuclear weapons, the only country to use them in warfare, a permanent member of the United Nations Security Council. Sweeping civil rights legislation, notably the Civil Rights Act of 1964, the Voting Rights Act of 1965 and the Fair Housing Act of 1968, outlawed discrimination based on race or color. During the Cold War, the United States and the Soviet Union competed in the Space Race, culminating with the 1969 U. S. Moon landing; the end of the Cold War and the collapse of the Soviet Union in 1991 left the United States as the world's sole superpower. The United States is the world's oldest surviving federation, it is a representative democracy.
The United States is a founding member of the United Nations, World Bank, International Monetary Fund, Organization of American States, other international organizations. The United States is a developed country, with the world's largest economy by nominal GDP and second-largest economy by PPP, accounting for a quarter of global GDP; the U. S. economy is post-industrial, characterized by the dominance of services and knowledge-based activities, although the manufacturing sector remains the second-largest in the world. The United States is the world's largest importer and the second largest exporter of goods, by value. Although its population is only 4.3% of the world total, the U. S. holds 31% of the total wealth in the world, the largest share of global wealth concentrated in a single country. Despite wide income and wealth disparities, the United States continues to rank high in measures of socioeconomic performance, including average wage, human development, per capita GDP, worker productivity.
The United States is the foremost military power in the world, making up a third of global military spending, is a leading political and scientific force internationally. In 1507, the German cartographer Martin Waldseemüller produced a world map on which he named the lands of the Western Hemisphere America in honor of the Italian explorer and cartographer Amerigo Vespucci; the first documentary evidence of the phrase "United States of America" is from a letter dated January 2, 1776, written by Stephen Moylan, Esq. to George Washington's aide-de-camp and Muster-Master General of the Continental Army, Lt. Col. Joseph Reed. Moylan expressed his wish to go "with full and ample powers from the United States of America to Spain" to seek assistance in the revolutionary war effort; the first known publication of the phrase "United States of America" was in an anonymous essay in The Virginia Gazette newspaper in Williamsburg, Virginia, on April 6, 1776. The second draft of the Articles of Confederation, prepared by John Dickinson and completed by June 17, 1776, at the latest, declared "The name of this Confederation shall be the'United States of America'".
The final version of the Articles sent to the states for ratification in late 1777 contains the sentence "The Stile of this Confederacy shall be'The United States of America'". In June 1776, Thomas Jefferson wrote the phrase "UNITED STATES OF AMERICA" in all capitalized letters in the headline of his "original Rough draught" of the Declaration of Independence; this draft of the document did not surface unti
Mexican prairie dog
The Mexican prairie dog is a diurnal burrowing rodent native to Mexico. Treatment as an agricultural pest has led to its status as an endangered species, they are related to squirrels and marmots. Cynomys mexicanus originated about 230,000 years ago from a peripherally isolated population of the more widespread Cynomys ludovicianus; these prairie dogs prefer to inhabit rock-free soil in plains at an altitude of 1,600–2,200 m. They are found in the regions of southern Coahuila and northern San Luis Potosí in northern Mexico, where they eat herbs and grasses native to the plains where they live, they acquire all of their water from these plants. Although herbivores, they have been known to eat insects. Predators include coyotes, eagles, badgers and weasels. Northern prairie dogs hibernate and have a shorter mating season, which lasts from January to April. After one month's gestation, females give birth to one litter per year, an average of four hairless pups, they are born with eyes closed and use their tails as visual aids until they can see, about 40 days after birth.
Weaning occurs during early June, when yearlings may break away from the burrow. Pups leave their mothers by fall; as they grow older, young play fighting games that involve biting and tackling. They reach sexual maturity with a lifespan of 3 -- 5 years, their coloring is yellowish, with a lighter belly. Prairie dogs have one of the most sophisticated languages in the animal world—a system of high-pitched yips and barks—and can run up to 35 miles per hour; as a consequence, their defense mechanism is to sound the alarm, get away quickly. Mexican prairie dogs live in excavated colonies, referred to as "towns", which they dig for shelter and protection. A typical town has a funnel-like entrance that slants down into a corridor up to 100 ft long, with side chambers for storage and nesting. Towns can contain hundreds of animals, but have fewer than 50, with a single alpha male. Sometimes, spotted ground squirrels or burrowing owls share the burrow with its rightful owners. In 1956, the Mexican prairie dog was reported as occurring in Coahuila, Nuevo León, San Luis Potosí.
By the 1980s, it had disappeared from Nuevo León, its complete range was less than 800 km2. Viewed as a pest and an obstacle to agriculture and cattle raising, it was poisoned, became endangered in 1994. Mexican prairie dogs inhabit less than 4% of their former territory; the current habitat of Mexican prairie dogs is in the region known as El Tokio. These are the grasslands located in the convergence of the states of San Luis Potosí, Nuevo León, Coahuila. Conservation groups such as Pronatura Noreste and Profauna, with the help of donors, carry out conservation efforts for the protection of prairie dogs and associated species, such as shorebirds and birds of prey. Pronatura Noreste, as of February 2007, has signed conservation easements with ejidos and private owners for the protection of more than 42,000 acres of Mexican prairie dog grasslands. ARKive - images and movies of the Mexican prairie dog Animal Info: Mexican prairie dog DesertUSA: Prairie dogs Prairie dogs videos Pronatura Noreste in the Chihuahuan Desert
Texas is the second largest state in the United States by both area and population. Geographically located in the South Central region of the country, Texas shares borders with the U. S. states of Louisiana to the east, Arkansas to the northeast, Oklahoma to the north, New Mexico to the west, the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the southwest, while the Gulf of Mexico is to the southeast. Houston is the most populous city in Texas and the fourth largest in the U. S. while San Antonio is the second-most populous in the state and seventh largest in the U. S. Dallas–Fort Worth and Greater Houston are the fourth and fifth largest metropolitan statistical areas in the country, respectively. Other major cities include Austin, the second-most populous state capital in the U. S. and El Paso. Texas is nicknamed "The Lone Star State" to signify its former status as an independent republic, as a reminder of the state's struggle for independence from Mexico; the "Lone Star" can be found on the Texan state seal.
The origin of Texas's name is from the word taysha. Due to its size and geologic features such as the Balcones Fault, Texas contains diverse landscapes common to both the U. S. Southern and Southwestern regions. Although Texas is popularly associated with the U. S. southwestern deserts, less than 10% of Texas's land area is desert. Most of the population centers are in areas of former prairies, grasslands and the coastline. Traveling from east to west, one can observe terrain that ranges from coastal swamps and piney woods, to rolling plains and rugged hills, the desert and mountains of the Big Bend; the term "six flags over Texas" refers to several nations. Spain was the first European country to claim the area of Texas. France held a short-lived colony. Mexico controlled the territory until 1836 when Texas won its independence, becoming an independent Republic. In 1845, Texas joined the union as the 28th state; the state's annexation set off a chain of events that led to the Mexican–American War in 1846.
A slave state before the American Civil War, Texas declared its secession from the U. S. in early 1861, joined the Confederate States of America on March 2nd of the same year. After the Civil War and the restoration of its representation in the federal government, Texas entered a long period of economic stagnation. Four major industries shaped the Texas economy prior to World War II: cattle and bison, cotton and oil. Before and after the U. S. Civil War the cattle industry, which Texas came to dominate, was a major economic driver for the state, thus creating the traditional image of the Texas cowboy. In the 19th century cotton and lumber grew to be major industries as the cattle industry became less lucrative, it was though, the discovery of major petroleum deposits that initiated an economic boom which became the driving force behind the economy for much of the 20th century. With strong investments in universities, Texas developed a diversified economy and high tech industry in the mid-20th century.
As of 2015, it is second on the list of the most Fortune 500 companies with 54. With a growing base of industry, the state leads in many industries, including agriculture, energy and electronics, biomedical sciences. Texas has led the U. S. in state export revenue since 2002, has the second-highest gross state product. If Texas were a sovereign state, it would be the 10th largest economy in the world; the name Texas, based on the Caddo word táyshaʼ "friend", was applied, in the spelling Tejas or Texas, by the Spanish to the Caddo themselves the Hasinai Confederacy, the final -s representing the Spanish plural. The Mission San Francisco de los Tejas was completed near the Hasinai village of Nabedaches in May 1690, in what is now Houston County, East Texas. During Spanish colonial rule, in the 18th century, the area was known as Nuevo Reino de Filipinas "New Kingdom of the Philippines", or as provincia de los Tejas "province of the Tejas" also provincia de Texas, "province of Texas", it was incorporated as provincia de Texas into the Mexican Empire in 1821, declared a republic in 1836.
The Royal Spanish Academy recognizes both spellings and Texas, as Spanish-language forms of the name of the U. S. State of Texas; the English pronunciation with /ks/ is unetymological, based in the value of the letter x in historical Spanish orthography. Alternative etymologies of the name advanced in the late 19th century connected the Spanish teja "rooftile", the plural tejas being used to designate indigenous Pueblo settlements. A 1760s map by Jacques-Nicolas Bellin shows a village named Teijas on Trinity River, close to the site of modern Crockett. Texas is the second-largest U. S. state, with an area of 268,820 square miles. Though 10% larger than France and twice as large as Germany or Japan, it ranks only 27th worldwide amongst country subdivisions by size. If it were an independent country, Texas would be the 40th largest behind Zambia. Texas is in the south central part of the United States of America. Three of its borders are defined by rivers; the Rio Grande forms a natural border with the Mexican states of Chihuahua, Nuevo León, Tamaulipas to the south.
The Red River forms a natural border with Arkansas to the north. The Sabine River forms a natural border with Louisiana to the east; the Texas Panhandle has an eastern border with Oklahoma at 100° W, a northern border with Oklahoma at 36°30' N and a western
Mexico the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States. Covering 2,000,000 square kilometres, the nation is the fifth largest country in the Americas by total area and the 13th largest independent state in the world. With an estimated population of over 120 million people, the country is the eleventh most populous state and the most populous Spanish-speaking state in the world, while being the second most populous nation in Latin America after Brazil. Mexico is a federation comprising 31 states and Mexico City, a special federal entity, the capital city and its most populous city. Other metropolises in the state include Guadalajara, Puebla, Tijuana and León. Pre-Columbian Mexico dates to about 8000 BC and is identified as one of five cradles of civilization and was home to many advanced Mesoamerican civilizations such as the Olmec, Teotihuacan, Zapotec and Aztec before first contact with Europeans. In 1521, the Spanish Empire conquered and colonized the territory from its politically powerful base in Mexico-Tenochtitlan, administered as the viceroyalty of New Spain.
Three centuries the territory became a nation state following its recognition in 1821 after the Mexican War of Independence. The post-independence period was tumultuous, characterized by economic inequality and many contrasting political changes; the Mexican–American War led to a territorial cession of the extant northern territories to the United States. The Pastry War, the Franco-Mexican War, a civil war, two empires, the Porfiriato occurred in the 19th century; the Porfiriato was ended by the start of the Mexican Revolution in 1910, which culminated with the promulgation of the 1917 Constitution and the emergence of the country's current political system as a federal, democratic republic. Mexico has the 11th largest by purchasing power parity; the Mexican economy is linked to those of its 1994 North American Free Trade Agreement partners the United States. In 1994, Mexico became the first Latin American member of the Organisation for Economic Co-operation and Development, it is classified as an upper-middle income country by the World Bank and a newly industrialized country by several analysts.
The country is considered both a regional power and a middle power, is identified as an emerging global power. Due to its rich culture and history, Mexico ranks first in the Americas and seventh in the world for number of UNESCO World Heritage Sites. Mexico is an ecologically megadiverse country, ranking fourth in the world for its biodiversity. Mexico receives a huge number of tourists every year: in 2018, it was the sixth most-visited country in the world, with 39 million international arrivals. Mexico is a member of the United Nations, the World Trade Organization, the G8+5, the G20, the Uniting for Consensus group of the UN, the Pacific Alliance trade bloc. Mēxihco is the Nahuatl term for the heartland of the Aztec Empire, namely the Valley of Mexico and surrounding territories, with its people being known as the Mexica, it is believed to be a toponym for the valley which became the primary ethnonym for the Aztec Triple Alliance as a result, although it could have been the other way around.
In the colonial era, back when Mexico was called New Spain this territory became the Intendency of Mexico and after New Spain achieved independence from the Spanish Empire it came to be known as the State of Mexico with the new country being named after its capital: the City of Mexico, which itself was founded in 1524 on top of the ancient Mexica capital of Mexico-Tenochtitlan. Traditionally, the name Tenochtitlan was thought to come from Nahuatl tetl and nōchtli and is thought to mean "Among the prickly pears rocks". However, one attestation in the late 16th-century manuscript known as "the Bancroft dialogues" suggests the second vowel was short, so that the true etymology remains uncertain; the suffix -co is the Nahuatl locative, making the word a place name. Beyond that, the etymology is uncertain, it has been suggested that it is derived from Mextli or Mēxihtli, a secret name for the god of war and patron of the Mexica, Huitzilopochtli, in which case Mēxihco means "place where Huitzilopochtli lives".
Another hypothesis suggests that Mēxihco derives from a portmanteau of the Nahuatl words for "moon" and navel. This meaning might refer to Tenochtitlan's position in the middle of Lake Texcoco; the system of interconnected lakes, of which Texcoco formed the center, had the form of a rabbit, which the Mesoamericans pareidolically associated with the moon rabbit. Still another hypothesis suggests that the word is derived from Mēctli, the name of the goddess of maguey; the name of the city-state was transliterated to Spanish as México with the phonetic value of the letter x in Medieval Spanish, which represented the voiceless postalveolar fricative. This sound, as well as the voiced postalveolar fricative, represented by a j, evolved into a voiceless velar fricative during the 16th century; this led to the use of the variant Méjico in many publications in Spanish, most notably in Spain, whereas in Mexico and most other Spanish–speaking countries, México was the preferred spelling. In recent years, the Real Academia Española, which regulates the Spanish l
Utah prairie dog
The Utah prairie dog is the smallest species of prairie dog, a member of the squirrel family of rodents native to the south central steppes of the US state of Utah. The fur is multicolor, which consists of black and dark brown at the tip. Face have dark brown cheeks and whitish tone of chins and mouth; the total body length of typical adult ranges from 30.5 cm to 36.0 cm with 3 cm to 6 cm of tail. Adult prairie dogs weigh about 0.77 kg to 1.41 kg in males, 0.64 kg to 1.13 kg in females. Utah prairie dogs show sexual dimorphism that males are 27% bigger than female, although the ratio varies by season. In 1952, Durant noted that Utah prairie dogs have larger in every aspect of skull than that of Gunnison's prairie dog. Utah prairie dogs prefer swale land area with abundant herbaceous plants, they build burrows on soils with adequate drain ability, depth to protect themselves from predators and other environmental factors such as temperature. Utah prairie dogs are only found in the southern part of Utah.
However, it was recorded that Utah prairie dogs existed as far north as Nephi, south to Bryce Canyon National Park, Aquarius Plateau to the east in 1920, but the number declined from the 1920s to 1970s by 87%, this was thought due to human settlers who caused overgrazing of soil, thus catalyzed the invasion of shrub to the grass land. Utah prairie dogs are herbivores, but they sometimes choose small insects such as cicadas. and prefer grasses but they do consume flowers in shrubs. Utah prairie dogs choose only few species of grasses only. Utah prairie dog shows polyandry behavior, lays only one litter per year, which consists of 1 to 8 litter size; the breeding occurs from mid-March through early April. They build extensive "towns" of underground tunnels and chambers, each town composed of a population of members of an extended prairie dog family group called “clan”, they forage from dawn to dusk; the species appears in the IUCN Red List of Threatened Species, with a status of Endangered, last assessed in 2008.
The Utah prairie dog is listed as a threatened species by the United States Fish and Wildlife Service. In 1972, studies estimated a population of 3,300 Utah prairie dogs in 37 colonies. Studies by the Utah Division of Wildlife Resources in spring 2004 reported 4,022 Utah prairie dogs, a number believed to reflect half of the total current population; the Utah prairie dog can do significant damage to farms by digging holes and eating crops, drawing the ire of Utah farmers, who have used poison liberally to destroy the animal. This is a major reason for the population decline, though there are other factors, such as "land development, deteriorating rangeland health, the encroachment of woody vegetation, sylvatic plague, drought." Conservation efforts include encouraging landowners to improve the health of their rangelands, compensating farmers who set aside areas the prairie dogs may use. Smithsonian: North American Mammals: Cynomys parvidens Mammalian Species account for Utah prairie dog Audio recordings of the Utah Prairie Dog Videos of Prairie dogs
Mammals are vertebrate animals constituting the class Mammalia, characterized by the presence of mammary glands which in females produce milk for feeding their young, a neocortex, fur or hair, three middle ear bones. These characteristics distinguish them from reptiles and birds, from which they diverged in the late Triassic, 201–227 million years ago. There are around 5,450 species of mammals; the largest orders are the rodents and Soricomorpha. The next three are the Primates, the Cetartiodactyla, the Carnivora. In cladistics, which reflect evolution, mammals are classified as endothermic amniotes, they are the only living Synapsida. The early synapsid mammalian ancestors were sphenacodont pelycosaurs, a group that produced the non-mammalian Dimetrodon. At the end of the Carboniferous period around 300 million years ago, this group diverged from the sauropsid line that led to today's reptiles and birds; the line following the stem group Sphenacodontia split off several diverse groups of non-mammalian synapsids—sometimes referred to as mammal-like reptiles—before giving rise to the proto-mammals in the early Mesozoic era.
The modern mammalian orders arose in the Paleogene and Neogene periods of the Cenozoic era, after the extinction of non-avian dinosaurs, have been among the dominant terrestrial animal groups from 66 million years ago to the present. The basic body type is quadruped, most mammals use their four extremities for terrestrial locomotion. Mammals range in size from the 30–40 mm bumblebee bat to the 30-meter blue whale—the largest animal on the planet. Maximum lifespan varies from two years for the shrew to 211 years for the bowhead whale. All modern mammals give birth to live young, except the five species of monotremes, which are egg-laying mammals; the most species-rich group of mammals, the cohort called placentals, have a placenta, which enables the feeding of the fetus during gestation. Most mammals are intelligent, with some possessing large brains, self-awareness, tool use. Mammals can communicate and vocalize in several different ways, including the production of ultrasound, scent-marking, alarm signals and echolocation.
Mammals can organize themselves into fission-fusion societies and hierarchies—but can be solitary and territorial. Most mammals are polygynous. Domestication of many types of mammals by humans played a major role in the Neolithic revolution, resulted in farming replacing hunting and gathering as the primary source of food for humans; this led to a major restructuring of human societies from nomadic to sedentary, with more co-operation among larger and larger groups, the development of the first civilizations. Domesticated mammals provided, continue to provide, power for transport and agriculture, as well as food and leather. Mammals are hunted and raced for sport, are used as model organisms in science. Mammals have been depicted in art since Palaeolithic times, appear in literature, film and religion. Decline in numbers and extinction of many mammals is driven by human poaching and habitat destruction deforestation. Mammal classification has been through several iterations since Carl Linnaeus defined the class.
No classification system is universally accepted. George Gaylord Simpson's "Principles of Classification and a Classification of Mammals" provides systematics of mammal origins and relationships that were universally taught until the end of the 20th century. Since Simpson's classification, the paleontological record has been recalibrated, the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself through the new concept of cladistics. Though field work made Simpson's classification outdated, it remains the closest thing to an official classification of mammals. Most mammals, including the six most species-rich orders, belong to the placental group; the three largest orders in numbers of species are Rodentia: mice, porcupines, beavers and other gnawing mammals. The next three biggest orders, depending on the biological classification scheme used, are the Primates including the apes and lemurs. According to Mammal Species of the World, 5,416 species were identified in 2006.
These were grouped into 153 families and 29 orders. In 2008, the International Union for Conservation of Nature completed a five-year Global Mammal Assessment for its IUCN Red List, which counted 5,488 species. According to a research published in the Journal of Mammalogy in 2018, the number of recognized mammal species is 6,495 species included 96 extinct; the word "mammal" is modern, from the scientific name Mammalia coined by Carl Linnaeus in 1758, derived from the Latin mamma. In an influential 1988 paper, Timothy Rowe defined Mammalia phylogenetically as the crown group of mammals, the clade consisting of the most recent common ancestor of living monotremes and therian m
Arizona is a state in the southwestern region of the United States. It is part of the Western and the Mountain states, it is the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona shares the Four Corners region with Utah and New Mexico. Arizona is the 48th state and last of the contiguous states to be admitted to the Union, achieving statehood on February 14, 1912, coinciding with Valentine's Day. Part of the territory of Alta California in New Spain, it became part of independent Mexico in 1821. After being defeated in the Mexican–American War, Mexico ceded much of this territory to the United States in 1848; the southernmost portion of the state was acquired in 1853 through the Gadsden Purchase. Southern Arizona is known for its desert climate, with hot summers and mild winters. Northern Arizona features forests of pine, Douglas fir, spruce trees. There are ski resorts in the areas of Flagstaff and Tucson. In addition to the Grand Canyon National Park, there are several national forests, national parks, national monuments.
About one-quarter of the state is made up of Indian reservations that serve as the home of 27 federally recognized Native American tribes, including the Navajo Nation, the largest in the state and the United States, with more than 300,000 citizens. Although federal law gave all Native Americans the right to vote in 1924, Arizona excluded those living on reservations in the state from voting until the state Supreme Court ruled in favor of Native American plaintiffs in Trujillo v. Garley; the state's name appears to originate from an earlier Spanish name, derived from the O'odham name alĭ ṣonak, meaning "small spring", which applied only to an area near the silver mining camp of Planchas de Plata, Sonora. To the European settlers, their pronunciation sounded like "Arissona"; the area is still known as alĭ ṣonak in the O'odham language. Another possible origin is the Basque phrase haritz ona, as there were numerous Basque sheepherders in the area. A native Mexican of Basque heritage established the ranchería of Arizona between 1734 and 1736 in the current Mexican state of Sonora, which became notable after a significant discovery of silver there, c.
1737. There is a misconception. For thousands of years before the modern era, Arizona was home to numerous Native American tribes. Hohokam and Ancestral Puebloan cultures were among the many that flourished throughout the state. Many of their pueblos, cliffside dwellings, rock paintings and other prehistoric treasures have survived, attracting thousands of tourists each year; the first European contact by native peoples was with Marcos de Niza, a Spanish Franciscan, in 1539. He explored parts of the present state and made contact with native inhabitants the Sobaipuri; the expedition of Spanish explorer Coronado entered the area in 1540–1542 during its search for Cíbola. Few Spanish settlers migrated to Arizona. One of the first settlers in Arizona was José Romo de Vivar. Father Kino was the next European in the region. A member of the Society of Jesus, he led the development of a chain of missions in the region, he converted many of the Indians to Christianity in the Pimería Alta in the 1690s and early 18th century.
Spain founded presidios at Tubac in 1752 and Tucson in 1775. When Mexico achieved its independence from the Kingdom of Spain and its Spanish Empire in 1821, what is now Arizona became part of its Territory of Nueva California known as Alta California. Descendants of ethnic Spanish and mestizo settlers from the colonial years still lived in the area at the time of the arrival of European-American migrants from the United States. During the Mexican–American War, the U. S. Army occupied the national capital of Mexico City and pursued its claim to much of northern Mexico, including what became Arizona Territory in 1863 and the State of Arizona in 1912; the Treaty of Guadalupe Hidalgo specified that, in addition to language and cultural rights of the existing inhabitants of former Mexican citizens being considered as inviolable, the sum of US$15 million dollars in compensation be paid to the Republic of Mexico. In 1853, the U. S. acquired the land south below the Gila River from Mexico in the Gadsden Purchase along the southern border area as encompassing the best future southern route for a transcontinental railway.
What is now known as the state of Arizona was administered by the United States government as part of the Territory of New Mexico until the southern part of that region seceded from the Union to form the Territory of Arizona. This newly established territory was formally organized by the Confederate States government on Saturday, January 18, 1862, when President Jefferson Davis approved and signed An Act to Organize the Territory of Arizona, marking the first official use of the name "Territory of Arizona"; the Southern territory supplied the Confederate government with men and equipment. Formed in 1862, Arizona scout companies served with the Confederate States Army duri