L. Boyd Finch's Confederate Pathway to the Pacific: Major Sherod Hunter and Arizona Territory, C.S.A [The Arizona Historical Society, 1996 (OP)] is about as definitive an account of Confederate Arizona as we are likely to get. The territory, stretching from California to Texas (think of an east-west running line splitting in half the area comprising the present states of New Mexico and Arizona instead of the current border), would be the object of many schemes for the expansion of the Confederate state to the Pacific coast.
Confederate Pathway to the Pacific is a deeply researched and well-written study. Finch does a wonderful job of 'setting the stage' for his later narrative of the war years. He traces the early settlement and nascent economic development of the region, noting the creation of a Southern-leaning "Arizonian" identity among many of the territory's most prominent citizens. The situation of the various Indian groups in relation to the settlers and each other is also detailed (especially the many conflicts with local Apache bands).
No major battles were fought between opposing Union and Confederate forces in Arizona. When Henry H. Sibley invaded New Mexico, he detached Capt. Sherod Hunter's company for an advance west into Arizona. Soon, Hunter was ensconced in Tucson. This move served both to guard the left flank of Sibley's main army as it advanced north into New Mexico and to secure the newly created Arizona territory for the C.S.A. However, when the U.S. army's "California Column" advanced into Arizona from Fort Yuma, the vastly outnumbered Confederates were soon ejected. The Union territorial occupation was relatively easy, with logistical problems holding up the advance more than any other factor. The affair at Picacho Pass, a picket post skirmish at best, was the most prominent military action [Flint Whitlock, in his book Distant Bugles, Distant Drums: The Union Response to the Confederate Invasion of New Mexico, modestly recommends Finch's book as the best account of Picacho Pass, but it is really only marginally more detailed than Whitlock's own recounting of events at the pass].
With the failure of Sibley's 1861-1862 New Mexico campaign, Confederate troops were shifted to other fronts, mainly the Gulf coast and east Texas. However, this did not stop various civilians and military officers from scheming to regain the lost territory of Arizona. Finch outlines these plans in the text, and details how and why none ever came to fruition--or ever really enjoyed serious support from the Confederate government. The last section deals with the post-war lives of the various figures who played prominent roles in Confederate Arizona.
For those as interested as I am in the Civil War's Far West,
Confederate Pathway to the Pacific is really a great book and merits an enthusiastic recommendation. Its high quality research, writing, and content are augmented by a beautiful presentation--the publisher, The Arizona Historical Society, deserves a lot of credit here for going the extra mile. I sincerely hope this worthy study will be reprinted in the future.