In 1862, the Confederacy made an incursion into New Mexico, into what had somewhat optimistically been dubbed the Confederate Arizona Territory in 1861. The Territory included parts of Arizona and New Mexico. The Confederate general in charge of the incursion was Brigadier General Henry Hopkins Sibley, who (effectively) had about 2,600 men. Arrayed against him were the forces of Union Colonel (later Major General) Edward Canby, with about 5,000 men. While the number of forces was fairly insignificant by Civil War standards (no Grant or Sherman size armies here), the stakes were remarkably high, especially to have such an obscure General like Sibley leading one side, and an equally obscure colonel leading the other. If the Confederates had been successful in their invasion of New Mexico, Colorado, Nevada and California might have been next, with all of the mineral wealth contained therein. If the Confederacy could have seized some of that mineral wealth, they could have financed the War indefinitely. The final deciding battle of the campaign, Glorieta Pass, is sometimes called the "Gettysburg of the West", because it was the high water mark of the Confederate incursion into the southwest. But from a strategic standpoint, it might have been as important as Gettysburg. The Union didn't win the Civil War by winning the Battle of Glorieta, but it could have lost the War by losing this battle.The book includes 33 photos/maps.