QUESTION: Usually it was common to see regiments from certain states like the 28th Massachusetts or 1st minnesota. What about the regular union army regiments. Where and how do those men sign up? Do they sign up and vary from different states as backgrounds?
ANSWER: I am not sure I understand the question, let me know if this is not what you are asking: At the start of the war the US Army had around 16,000 men while I hate Wikipedia (someone who knew what they were doing did this page- so quick before some smart butt screws it up look it up, you'll find like their Confederate counterpart just about every unit was referenced as a State (Texas Brigade), an individual (Mosbys' Rangers) or after an object (Palmetto State). While I have not been able to find the originality of these 16,000 men I will bet you they were from an area. Just about all units even into WW I were made up of men from one location, they felt it made a better more cohesive force, they were less likely to run and it made the men less homesick. I am not sure they did not have the right idea. While I don't believe the war was over "States Rights" with men on both sides preferring to be in their States unit makes you wonder how much loyalty they really had toward a central power. I saw more barrack fights over someone saying Oregon was better than South Dakota; then I care to remember.
Is this answer your question? By the way if you are interested in the War there a unique group on Face Book called the Southern Heritage Preservation Group but don't let the name fool you, it is a Civil War Roundtable designed to dispel rumors and myths. I hope we answered you question please tell your family and friends about our services.
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QUESTION: Could a private or other low ranking non commissioned officers be promoted to officer during the war? If so, do they stay in the same regiment that they were in or get transferred to another unit?
It was curious that you asked this question when you did. We were just discussing Battle Field Commissions, mustangs and brevet. This has nothing to do with your questions but I hope you will find it informative; A mustang is Military slang for a commissioned officer who began his or her career as an enlisted person. Brevet was carried over from the British and discontinued after the war, it basically rewarded an officer for a deed, action, superior performance by awarding them a higher grade than they were; it was very confusing. A good example was Custer who was a major general of volunteers, a lieutenant colonel in the Regular Army, and brevet commissions as major general of volunteers and major general in the Regular Army.
To address your exact question it is called a “battlefield commission” and as near as I can find the program ran all the way to Nam. Yes, an enlisted man could be promoted by his superiors usually for bravery but also if they proved themselves exceptional. They would try to keep them in their original unit. However if due to conflicts or open positions they might be placed in another unit. There was another way to be promoted (besides West Point) your unit could vote you whatever rank was open or due to incompetency was coming open. Please feel free to contact me if you need additional information.
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