New Mexico is a landlocked state in the Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also borders the state of Texas to the east and southeast, Oklahoma to the northeast, and shares an international border with the Mexican states of Chihuahua and Sonora to the south. New Mexico's largest city is Albuquerque, and its state capital is Santa Fe, the oldest state capital in the U.S.—founded in 1610 as the government seat of Nuevo México in New Spain—and the highest in elevation, at 7,000 feet (2,134 m).

New Mexico is the fifth-largest of the fifty states by area, but with just over 2.1 million residents, ranks 36th in population and 45th in population density. Its climate and geography are highly varied, ranging from forested mountains to sparse deserts; the northern and eastern regions exhibit a colder alpine climate, while the west and south are warmer and more arid. The Rio Grande and its fertile valley runs north-to-south, creating a riparian biome through the center of the state that supports a bosque habitat and distinct Albuquerque Basin climate. One-third of New Mexico's land is federally owned, including many protected wilderness areas, 15 national parks and monuments, and three UNESCO World Heritage Sites wholly contained within the state—the most of any U.S. state.

Since time immemorial, New Mexico was home to Pueblo peoples, the Mogollon culture, and Ute. The Pueblo peoples occupied several dozen villages, mostly in northern New Mexico's Rio Grande valley. The Navajo and Apache arrived in the late 1400s, the Spanish in 1598, and the Comanche in the early 1700s. The Spanish colony of Nuevo México became a peripheral part of the viceroyalty of New Spain. The 1680 Pueblo Revolt was the first successful revolution against colonial rule in the Americas. In 1692 Spanish colonial rule returned, but the colony fell under the influence of Comancheria with the Comanche-Spanish peace treaties of 1785 and 1786, isolated by its rugged terrain and distance from Mexico City. Upon Mexican independence in 1821, New Mexico became an autonomous territory that saw an 1837 Rebellion against the central government, with increasing economic ties to the United States. After the Mexican–American War in 1848, the U.S. annexed New Mexico as part of the larger New Mexico Territory, which was central to U.S. westward expansion. New Mexico was a territory for 64 years before it was admitted to the Union as the 47th state on January 6, 1912. During World War II, New Mexico hosted several key facilities of the Manhattan Project, which developed the world's first atomic bomb, and was the site of the first nuclear test, Trinity in 1945. (Full article...)