U.S. Territorial Period

Explore the U.S. Territorial time period


1848 Treaty of Guadalupe Hidalgo
The 1848 Treaty of Guadalupe Hidalgo ended the war between the United States and Mexico. By its terms, Mexico lost almost half of its territory, including parts of present-day Arizona, California, New Mexico, Texas, Colorado, Nevada, and Utah.
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1850 New Mexico becomes a US territory
The Compromise of 1850 grants New Mexico territorial status on 9 September 1850. President Millard Fillmore signs into law the Organic Act, admitting New Mexico into the Union as a territory and allowing for the formation of a territorial government.

1851 Jean Baptiste Lamy arrives
The French Roman Catholic priest destined to become Bishop and later Archbishop of Santa Fe arrives in August. Father Juan Felipe Ortiz informs Lamy that he and other New Mexican priests remain loyal to the Bishop of Durango, Mexico. Read More

1854 Gadsden Purchase
US pays Mexico $10 million for 29,670 square miles of Mexican territory that becomes part of Arizona and New Mexico, giving the US a route for a southern transcontinental railroad and ownership of the copper mines at Santa Rita.

1862 Civil War Battles in New Mexico
Major engagements in New Mexico include battles at Valverde in February and Glorieta Pass in March. The encounter at Glorieta Pass stops the Confederate advance in the Southwest and proves to be the turning point of the war in New Mexico.

1864 Navajo Long Walk
Beginning in January, some 8,000 to 9,000 Navajos are forced to relocate from their homeland to an internment camp at Bosque Redondo, walking 450 miles in eighteen days. At least two hundred Navajos perish on the Long Walk. Read More

1879 Railroad reaches New Mexico
The first passenger train into New Mexico carries members of the Colorado legislature to Otero on the Atchison, Topeka, and Santa Fe Railroad line on 13 February 1879. One year later, the line is extended through Mora, San Miguel, and Santa Fe Counties.

1888-89 State universities established
Founded in 1888, Las Cruces College becomes New Mexico College of Agriculture and Mechanic Arts in 1899 and New Mexico State University in 1960. The University of New Mexico is founded in 1889 upon the passage of New Mexico House Bill 186.