I posted this on a May 2005 thread but I still think it is one of the most powerful songs of the era.

Write a Letter to My Mother          E. Bowers 1864

Raise me in your arms, my brother
Let me see the glorious sun
I am very faint and dying
Was the battle lost, or won?

I remember you, my brother,
Who sent to me that fatal dart
Brother fighting, yea, against brother
Perhaps 'tis best that thus we part      

Chorus:
Write a letter to my mother,
Tell her that her boy is dead.
That he perished by his brother,
Not a word of that be said      

Father's fighting for the Union
You may meet him on the field
Would you raise your arm and smite him
Would you bid your father yield?

He who loved us in our childhood
Taught the infant prayers we said
Brother, take from me this warning
I'd sooner be among the dead

Do you ever think of Mother,
In our home within the glen,
Watching, praying for her children,
Would you see that home again?

Brother, I am surely dying.
Keep the secret, for 'tis one
That would kill our angel mother,
If she but knew what you have done,