I have read, forgotten, and reread just how many men went into any given Civil War formation many times. They all sound so similar to my civilian ears that keeping them straight requires a lot of work even before allowing for how strength on paper rarely matched strength on the ground. But here’s Gary Adelman explaining it:
Mind how he refers to units coming from the same town or county. Recruiting generally went that way, with predictable results when a unit really got hit hard.