Dave Powell's trilogy on the Chickamauga campaign are on sale for $2.99 each for the Kindle on amazon. https://www.amazon.com/David-Powell/e/B004JA1AWO

Highly appreciate the tip!I haven't seen anything particular to the kings, but the two decent books on the period I've found are:
Before France and Germany: The Creation and Transformation of the Merovingian World
The Merovingian Kingdoms 450–751
I wouldn't consider either of them great, but they're what I know of.
it is a scary read.Mein kampf. Been meaning to for years. Frightening read.
Generations have read this so that you don't have to. But if you have new insights let us know.Mein kampf. Been meaning to for years. Frightening read.
My uncle collected books like these.
Wolverines!!!!Reading Red Dawn by Ralph Peters. I'm nearly done with it. Not bad. At the same time I'm playing Compass games' "Brezhnev's War." I'm five turns in (out of 10) and am enjoying the game much.