Going through a list of the classic American Westerns I was struck by how many of them invoked the civil war or ex-confederates as part of the characterization of major characters
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Historically, the Civil War loomed large in the Far West, but it was rather like watching one's favorite football team engaged in a struggle on the other side of the continent, the results of which can only be gained in a newspaper after the actual event. It was easy for Westerners to be consumed by news of battles because many had friends and relatives in 'the States' as they called the contiguous US of the East. At the same time, however, Westerners often didn't have an real 'skin in the game.' Many went West to avoid the draft, and regardless of how, when, and why they were in the West, there was little they could do to directly deal with the circumstance of the epic cataclysm.
A few examples from Nevada history can serve to illustrate how Westerners viewed the Civil War. One of the more famous incidents from the period in the West was the circumstance surrounding the Gridley Flour Sack in Austin, Nevada. Gridley backed the democratic candidate for mayor, and he bet a Republican friend on the outcome of the election, the loser promising to carry a fifty pound flour sack through town to the other. Gridley lost, so he carried his flour sack to its destination, at which point all concerned agreed that it should be auctioned, the proceeds going to the Sanitary Fund, which was an organization established to assist the wounded during the war. The sack sold for $250, but the new owner gave it back to Gridley to be auction again. And again. And again. The incident became famous and Gridley and his sack made the rounds to Virginia City and other places in the West, including in California, ultimately raising about $275,000, or more than $5 million in today's dollars. The incident provides a good example of how Westerners wanted to participate in some way, and when given the chance, gave mightily in dollars if not in blood.
Reading period newspaper, one gets a feel for the news that was received and how it was greedily digested. Often news of battles followed the event by a week or more since newspapers had to wait for the telegraph to transmit the contents of stories from Eastern newspapers. A particularly poignant incident occurred as one reporter in Virginia City recalled several days before on July 4, 1863, when there was a looming black cloud that darkened the town, but that the sun's rays broke through it all to illuminate the gigantic flag that flew atop Mount Davidson, at its peak 1,600 feet above town. The reporter recalled how people looked at the awesome image and speculated that it seemed to be an ominous sign of something significant. The reporter then went on to say that when they finally received news of the Fall of Vicksburg and of the Battle at Gettysburg, all unfolding on the 4th, that the significance of that inspiring vision seemed to make sense.
There was also an incident following the news of the July 18, 1863 Battle for Fort Wagner, which famously (celebrated in the film 'Glory') involved the African-American 54th Massachusetts Volunteer Infantry. The news focused on the fact that Brigadier General George C. Strong had been mortally wounded in the battle (he died two weeks later), noting that his brother Charles Strong, Superintendent of the Gould and Curry Mine, had suffered the loss of his family member. The article was silent on how the loss must have been felt by the African American community in Virginia City. William A. G. Brown, a free-born African American from Massachusetts owned and operated the 'Boston Saloon,' and it is easy to imagine that he too knew - and was perhaps related to - those who fell during the battle, but the primary records are silent on this score.
Finally, when the West received word of the assassination of President Lincoln in April 1865, the region was cast into mourning. In general, Southerners were a minority in the West - they represented about a quarter of the 'Americans' in Virginia City, which was itself composed largely of the foreign-born. And Southerners early on had learned to keep their support of the Confederacy to themselves - being about as popular as a Broncos fan in Dallas. At the beginning of the War, a few enthusiasts flew Secessionist flags in Virginia City, but they were quickly removed by the authorities, and the proponents of that point of view received stern and sometimes violent warning against that sort of activity. With Lincoln's death, feelings were high, and most were in deep mourning. Thousands turned out for a mock funeral parade and ceremony. When one Southerner in neighboring Gold Hill said that he was glad for the murder and wished it had come sooner, he nearly lost his life during the subsequent beating. The National Guard intervened, whipping the man and forcing him to march to Virginia City with a placard around his neck declaring him to be a traitor. If it had not been for the National Guard, it is likely that the man would have lost his life. His example no doubt encouraged anyone of like sentiment to remain quiet.
For all the rhetoric and high emotion, however, the West was very removed from action in the East. This was before the transcontinental railroad was completed in 1869, and travel East was simply too difficult. The West remained distant and with its own defensive needs since conflicts with Native American remained a real possibility. There are a few examples of Westerners heading East to join in the war - on both sides - but these were anomalies, and the fact that they were often commented upon demonstrates the scarcity of these examples. But the War was important for the West , which was consumed by the conflict, which it watched as well as it could.
This may not be the answer you seek, but I hope it helps.