Generalization
The standard U.S. Army uniform at the outbreak of the war had acquired its definitive form in the 1858 regulations. It consisted of a Campaign Uniform, a Parade Uniform, and a Fatigue Uniform.
During the war, enforcement of uniform regulations was imperfect. Uniforms were adapted to local conditions, the commander's preference and what was available. As a result almost any variation of the official uniform could be found as officers and men abandoned some items, adopted others and modified still others.
Described in general terms this uniform consisted of:
Read more about this topic: Uniform Of The Union Army