The New Mexico Territory, comprising what are today the U.S. states of New Mexico and Arizona, as well as the southern portion of Nevada, played a small...

nearly 62 years, the longest period of any territory in the contiguous United States. In 1846, during the Mexican–American War, the United States established...

Mesilla. After the start of the American Civil War, support for the Confederacy was strong in the southern part of the New Mexico Territory. Some residents...

Civil War Nevada in the American Civil War New Mexico Territory in the American Civil War Arizona Territory in the American Civil War The Bear River Massacre...

The New Mexico campaign was a military operation of the trans-Mississippi theater of the American Civil War from February to April 1862 in which Confederate...

The Utah Territory (September 9, 1850 - January 4, 1896) during the American Civil War was far from the main operational theaters of war, but still played...

Battles of the American Civil War were fought between April 12, 1861, and May 12–13, 1865 in 19 states, mostly Confederate (Alabama, Arkansas, Florida...

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

The Colorado Territory was formally created in 1861 shortly before the bombardment of Fort Sumter sparked the American Civil War. Although sentiments were...

The role of Washington Territory in the American Civil War is atypical, as the territory was the most remote from the main battlefields of the conflict...