Following the

Gadsden Purchase The Gadsden Purchase ( "La Mesilla sale") is a region of present-day southern Arizona and southwestern New Mexico that the United States acquired from Mexico by the Treaty of Mesilla, which took effect on June 8, 1854. The purchase included lan ...

, the

United States Army The United States Army (USA) is the primary Land warfare, land service branch of the United States Department of Defense. It is designated as the Army of the United States in the United States Constitution.Article II, section 2, clause 1 of th ...

sent Major Enoch Steen and four companies of the 1st U. S. Dragoons (now the 1st U. S. Cavalry) to occupy the former site of the Mexican

Presidio de Calabasas The Presidio de Calabasas, also known as Fort Calabasas or Camp Calabasas, was a stone fortress built by Mexico in 1837 south of Tumacacori, Arizona. It was built on the land of the Grant of Manuel María Gándara, by Gándara to protect his lan ...

. Major Steen arrived on November 27, 1856, and named his post Camp Moore. The dragoons put roofs on the old adobe structures and added a few new ones. Camp Moore was abandoned in March 1857 after another location in the San Rafael Valley was chosen for a permanent fort that was christened Fort Buchanan. With the coming of the

American Civil War The American Civil War (April 12, 1861May 26, 1865; also known by Names of the American Civil War, other names) was a civil war in the United States between the Union (American Civil War), Union ("the North") and the Confederate States of A ...

all military posts in western New Mexico Territory (now Arizona) were abandoned. Old Camp Moore at

Calabasas Calabasas may refer to: * Calabasas, Arizona, former populated place in what is now Rio Rico, Arizona * Calabasas, California, city in Los Angeles County, California See also * Calabaza Calabaza is the generic name in the Spanish langua ...

was briefly occupied by the Confederates in March 1862, just before the arrival of the

California Column The California Column was a force of Union volunteers sent to Arizona and New Mexico during the American Civil War. The command marched over from California through Arizona and New Mexico Territory to the Rio Grande and as far east as El Paso, ...

in April. The California Volunteers posted troops at

Tucson Tucson (; ; ) is a city in Pima County, Arizona, United States, and its county seat. It is the second-most populous city in Arizona, behind Phoenix, Arizona, Phoenix, with a population of 542,630 in the 2020 United States census. The Tucson ...

and Tubac, and established

Fort Bowie Fort Bowie was a 19th-century outpost of the United States Army located in southeastern Arizona near the present day town of Willcox, Arizona. The remaining buildings and site are now protected as Fort Bowie National Historic Site. Fort Bowi ...

. In September 1865 the garrison at

Tubac, Arizona Tubac is a census-designated place (CDP) in Santa Cruz County, Arizona, United States. The population was 1,191 at the 2010 census. The place name "Tubac" is an English borrowing from a Hispanicized form of the O'odham name ''Cuwak'', which ...

was transferred to Old Camp Moore at Calabasas and it was first named Post at Calabasas, then renamed Fort Mason in honor of General Mason, who was commander of the California Volunteers in Arizona. In 1866 it was briefly renamed Camp McKee. The

1st Battalion of Native Cavalry, California Volunteers The 1st Battalion of Native Cavalry, California Volunteers was a cavalry battalion in the Union Army during the American Civil War. Recruits were largely drawn from the Californio population (colloquially known as "Native Californians"), though i ...

and 7th Regiment California Volunteer Infantry occupied the post until they were relieved by troops of the

in May 1866. Due to persistent

malaria Malaria is a Mosquito-borne disease, mosquito-borne infectious disease that affects vertebrates and ''Anopheles'' mosquitoes. Human malaria causes Signs and symptoms, symptoms that typically include fever, Fatigue (medical), fatigue, vomitin ...

, the Regulars abandoned Fort Mason (now Camp McKee) in 1866 and established Camp Cameron.United States Military Posts on the Mexico Border (1856 to Present)
from archaeologysouthwest.org accessed July 21,2019 Camp Moore and Fort Mason were collocated south of the confluence of Potrero Creek and the Santa Cruz River. Camp Cameron was about 16 miles northeast of Fort Mason and existed from October 1, 1866 to March 7, 1867.Robert Frazer, Robert W. Frazer, ''Forts of the West: Military Forts and Presidios and Posts Commonly Called Forts West of the Mississippi River to 1898'', University of Oklahoma Press, 1975, p. 7
/ref>

References

{{reflist American frontier Archaeological sites in Arizona Buildings and structures in Santa Cruz County, Arizona History of Santa Cruz County, Arizona Mason, Arizona Territory 1865 establishments in Arizona Territory