The average age of soldiers who participated in the Civil War was about 25-26 years old, or generally men in their mid-twenties.
The exact calculated estimate is 25.8. However, this estimation mostly relies on Union records, because there isn't really any exact data recorded on the average age of Confederate soldiers. On the Confederate's side, it's thought that young boys and older men who wouldn't usually be drafted under normal circumstances were pressed into service. feelsbadman.
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