Patti and Ken,
I can't thank you both enough for the great information on Nathaniel. This has been a family mystery for 145 years. My ggf, George Marion Oquin went to Texas after the war to search for Nathaniel (Nathaniel was the youngest brother). After not finding him, George moved his family from MO to Mills County, TX (Goldthwaite) where he was a farmer and circuit-riding minister until his death in 1902. We are fortunate to have his CW diary and his enlistment photo as well as letters during the period between him and his other brothers in service with the Union Army, but had nothing on Nathaniel since he was the lone Confederate.
According to the family history I have, Nathaniel was born on May 10, 1842 in Lincoln County, TN. He was believed to have never married. The correct spelling is Oquin. Thanks again for the help. This is a great website!