Thanks for the recommendation.
Along with several others recommended on these threads, I've added yours to my laptop's e-library.
Another interesting book on this subject is William W. Freehling (2001-02-15). The South Vs. The South : How Anti-Confederate Southerners Shaped the Course of the Civil War.
"Statistics indicate other Southerners ability to cool white Confederates ardor; and the numbers illuminate but the tip of the iceberg.
Southern blacks supplied close to 150,000 Union soldiers and sailors (northern free blacks provided another 50,000).
Border South whites added 200,000 and Confederate state whites 100,000 soldiers to Union troop strength.
The resulting total of 450,000 Southerners who wore Union blue, half as many as the 900,000 Southerners who wore Confederate gray, replaced every one of the Federals 350,000 slain men and supplied 100,000 more men besides -- a number greater than the usual size of Robert E. Lees main Confederate army.
White Confederates developed no such replacements for their mounting casualties; and in addition, anti-Confederate Southerners piled on psychological, economic, and geographic burdens that ultimately helped flatten white Confederates resiliency."
A large part of my family comes from Southern areas which remained loyal to the Union.
They are the direct Southern equivalents of Northern Dough Face / Copperheads.
It's also interesting that in Vietnam, 30,000 CANADIANS served in the U.S. military in Vietnam---3 x the number that fled to Canada to avoid the draft.